Vol. 51, No. 1, 2003
CONTENTS
Review
- Apoptosis in Human Polymorphonuclear Leukocytes: Searching for a Genetic Roadmap
Scott D. Kobayashi and Frank R. DeLeo (Laboratory of Human Bacterial Pathogenesis, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA)Abstract. Polymorphonuclear leukocytes (PMNs or neutrophils) are essential components of the innate immune system in humans and function primarily to eliminate invading microorganisms. Neutrophil influx to sites of infection is desirable because it also initiates an inflammatory response. Paradoxically, PMNs are also intimately associated with inflammatory disease. As part of normal neutrophil turnover in humans and to limit inflammatory potential, PMNs undergo programmed cell death or apoptosis. Several host factors, including cytokines and growth factors, are capable of extending neutrophil survival, and thus capacity to fight infection. On the other hand, phagocytosis of bacterial pathogens generally accelerates PMN apoptosis. Due in part to the extensive complexity of programmed cell death, relatively little is known about signaling pathways that govern these processes in PMNs. Recently, microarray strategies have been employed to gain an understanding of these processes in activated PMNs, and new evidence indicates that gene transcription is important in the regulation of neutrophil apoptosis and thus inflammation. A series of provocative discoveries led to the hypothesis that neutrophil programmed cell death is the result of an apoptosis differentiation program, a final stage of transcriptionally regulated PMN maturation or hematopoietic differentiation. Further characterization of the apoptosis differentiation program and associated biochemical pathways in mature PMNs will likely yield important insights into the resolution of inflammation and infection.
Keywords: neutrophil; apoptosis; gene transcription; inflammation.
- BH3-Only Proteins: the Lords of Death
Aarne Fleischer, Angelita Rebollo and Verónica Ayllón (Laboratoire d’Immunologie Cellulaire et Tissulaire U543 INSERM, Bâtiment CERVI, Hôpital Pitié-Salpetriere, 83 Bd de l’Hôpital F-75651 Paris Cedex 13, France)Abstract. Although the mechanisms by which Bcl-2 family proteins control the apoptotic machinery of the cell are not fully understood, it becomes clear that the role of BH3-only proteins consists in serving as sensors or sentinels of cellular damage, transducing the apoptotic stimuli to the mitochondria. For this reason, mammalian cells have developed several strategies for their strict regulation throughout evolution. This review aims to highlight the different ways by which BH3-only proteins are controlled, including transcriptional regulation, post-translational modifications and subcellular localization.
Keywords: apoptosis, Bcl-2, BH3-only proteins, transcriptional regulation, post-translational modifications.
- Viral Modulation of Cell Death by Inhibition of Caspases
Uwe Cassens (Institute of Transfusion Medicine, University of Muenster, D-48149 Muenster, Germany), Grzegorz Lewinski (Unit of Surgery, Municipal Hospital, 38-300 Gorlice, Poland), Ajoy K. Samraj (Institute of Molecular Medicine, University of Duesseldorf, D-40225 Duesseldorf, Germany), Horst von Bernuth (Children’s University Clinic, Laboratory for Clinical Research, D-01307 Dresden, Gemany), Heinrich Baust (Department of Radiotherapy, University of Ulm, D-89070 Ulm, Germany), Khashayarsha Khazaie ((Department of Cancer Immunology and Aids, Dana Farber Cancer Institute/Harvard Medical School, Boston, MA 02115, USA) and Marek Los (Institute of Experimental Dermatology, University of Muenster, D-48149 Muenster, Germany)Abstract. Caspases are key effectors of the apoptotic process. Some of them play an important role in the immune system, being involved in proteolytic maturation of the key cytokines including interleukin-1beta (IL-1beta) and interleukin-18 (IL-18). The latter directs the production of interferon gamma (IFN-gamma). Among pathogens, particularly viruses express various modulators of caspases that inhibit their activity by direct binding. By evading the apoptotic process viruses can better control their production in the infected cell, and avoid the attack of immune system. Targeting of the maturation of the key cytokines involved in the initiation of (antiviral) immune response helps to avoid the recognition and eradication by the immune system. The three main classes of caspase inhibitors frequently found among viruses include serpins (CrmA/SPI-2), viral IAPs (vIAPs) and p35. Their molecular mechanism of action, structure and the overall influence on cellular physiology is discussed in the review below.
Keywords: CrmA; IAP; p35; caspase; granzyme B.
- Immune Mechanisms Contributing to Spontaneous Acceptance of Liver Transplants in Rodents and their potential for clinical transplantation
Marcel den Dulk1, 2 and G. Alex Bishop1 (1AW Morrow Gastroenterology and Liver Laboratory, Centenary Institute, Royal Prince Alfred Hospital and Sydney University, Sydney, Australia and 2Department of Surgery, Leiden University Medical Centre, Leiden, The Netherlands)Abstract. The fate of organ transplants between unrelated individuals of the same species is almost always to be rejected, unless the recipient receives immunosuppressive drugs. Liver transplants are an exception, as in a number of animal models, they are often accepted without requiring any treatment. Several mechanisms have been proposed for liver transplant acceptance including: the vascular structure of the liver which allows interaction between naive T cells and liver parenchymal cells; the atypical leucocyte populations of the liver particularly immature dendritic cells; neutralisation of rejection by donor soluble MHC antigen; establishment of microchimerism by donor haematopoietic stem cells and death by “neglect” of recipient T cells in response to inappropriate activation by donor liver leucocytes. Although all these mechanisms may contribute to liver acceptance to some degree, an important finding is that liver acceptance appears to be mainly due to donor leucocytes transplanted with the liver. In combination with the observation of rapid T cell activation followed by their death after liver transplantation, these findings have identified a prominent role for donor leucocyte-induced deletion of liver-reactive T cells. These findings suggest novel ways to explore improved treatment for transplant patients, including administration of donor leucocytes at the time of transplantation and delay of some components of immunosuppressive drug induction therapy.
Keywords: transplantation tolerance, liver transplantation, graft rejection, graft survival, immunosuppressive agents.
- Molecular Targets for Immunocontraception
Bogdana Stoyka1,2, Alina Domagala1 and Maciej Kurpisz1 (1Institute of Human Genetics, Polish Academy of Sciences, Poznań, Poland, 2 Danylo Halytsky State Medical University, Lviv, Ukraine)Abstract. An effective contraceptive is necessary in the countries where limiting population growth has become a public policy imperative. Main antigenic targets for contraceptive vaccine development can be listed as following: 1) sperm antigens; 2) zona pellucida antigens; 3) gonadotrophin-releasing hormone; 4) chorionic gonadotrophin; 5) other protein/peptide hormones (follicle-stimulating hormone, luteinising hormone, luteinizing hormone – releasing hormone); 6) gonadal steroid hormones. New techniques such as an application of monoclonal antibodies, hybridoma and DNA recombinant technologies became useful in search for contraceptive candidates. Current state of development of contraceptive vaccines based on specific antigenic targets and trials in animal/human models are presented in this article.
Keywords: immunocontraception; sperm; zona pellucida; hormonal antigenic targets.
Clinical Immunology
- Individual Differentiation of Innate Antiviral Immunity in Humans; the Role of Endogenous Interferons and Tumor Necrosis Factor in the Immunity of Leukocytes
Beata Orzechowska, Zenon Antoszków and Zofia Błach-Olszewska (Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Weigla 12, 53-112 Wrocław, Poland)Abstract. The natural antiviral immunity of human lymphocytes, leukocyte from peripheral blood and whole-blood cultures was studied using the method of infection with two viruses belonging to different taxonomic groups, vesicular stomatitis virus (VSV) and encephalomyocarditis virus (EMCV). The kinetics of virus replication in both kinds of cultures and the dependence of culture infection on pre-infection incubation time were studied. When the cultures were infected immediately after preparation, most of them were found to be resistant to the viruses. However, when they were infected after several (1-5) days of incubation, VSV and EMCV multiplied in the cultures to high titers. The time of losing the resistance was individually differentiated. The results indicate the presence of a non-specific antiviral immunity characteristic for individuals. The antiviral immunity of healthy donors was compared with that of people suffering from recurrent infections of the upper respiratory tract. This latter group expressed statistically significant lower innate immunity than healthy donors. However there were no differences in interferon (IFN) and tumor necrosis factor (TNF) production between these groups. In order to examine the contribution of the endogenous IFNs and TNF alpha in maintaining innate immunity, specific antibodies against IFN alpha, IFN beta, IFN gamma and TNF alpha were added to VSV-infected leukocytes resistant to infection. The antibodies reduced the antiviral resistance in 9 of 16 experiments. The results suggest that both: endogenous interferons and TNF alpha may participate in the constitution of innate immunity, though they are not the only mediators of it.
Keywords: innate immunity; human leukocytes; viral infections, interferons, tumor necrosis factor.
Immunopharmacology
- Effect of Cyclosporin A Used Alone and in Combination with either 2-Chlorodeoxyadenosine or Fludarabine on Normal and Chronic Myelogenous Leukemia Progenitors in Vitro
Anna Korycka and Tadeusz Robak (Department of Hematology, Medical University of Łódź, Pabianicka 62, 93-513 Łódź, Poland)Abstract. We evaluated the influence of cyclosporin A (CsA) used alone or together with new purine nucleoside analogues (PNAs): 2-chlorodeoxyadenosine (2-CdA) and fludarabine (F-ara-A) on the colony growth of normal and chronic myelogenous leukemia (CML) granulocyte-macrophage progenitor cells (CFU-GM) in cultures in vitro. The assay was based on the method described by Iscove et al. in our modification. Specimens of bone marrow were collected from 15 patients with CML in the chronic phase and from 10 hematologically normal patients. CsA at the concentrations of 1, 2 and 4 mg/ml was used alone and at the concentration of 4 mg/ml it was preincubated with MNCs and after 30 minutes PNAs were added to the culture medium. 2-CdA at the concentrations of 5, 10, 20 nM and 0.4, 0.8, 1.6 mM of F-ara-A were used. After 14 days of incubation the colonies were scored under inverted microscope. We observed that CsA used alone at all three concentrations in a statistically significant degree inhibited the colony growth of CML CFU-GM, as compared to the control (p<0.02) and it did not significantly influence the normal colony growth. IC50 for CsA was 3.9 mg/ml in case of normal CFU-GM and 2.7 mg/ml in case of CML CFU-GM. After the use of CsA in combination either with the highest concentrations of 2-CdA or F-ara-A, statistically significant differences, as compared to CsA used alone were observed (p=0.008; p=0.03 for CsA with 2-CdA; and p=0.0007; p=0.005 for CsA with F-ara-A; respectively for normal and CML CFU-GM). However, there were no significant differences between the combinations of drugs and PNAs used alone. In case of the combination of CsA with the highest concentrations of both PNAs significant differences in the colony growth inhibition between normal and CML CFU-GM were observed (p=0.002 and p=0.005, respectively for 2-CdA and F-ara-A). In conclusion, at the used concentrations of the drugs a subadditive action was observed either between CsA and 2-CdA or between CsA and F-ara-A.
Keywords: cyclosporin A; purine nucleoside analogues; chronic myelogenous leukemia; CFU-GM; cultures in vitro.
Immunochemistry
- Immunochemical studies on the O-antigens of Proteus mirabilis O23 and Proteus vulgaris O23
Antoni Różalski1, Andrei V. Perepelov2, Beata Bartodziejska1, Sof’ya N. Senchenkova2, Dorota Babicka1, Wieslaw Kaca1,3 and Yuriy A. Knirel2 (1Department of Immunobiology of Bacteria, Institute of Microbiology and Immunology, University of Łódź, Banacha 12/16, 90-237 Łódź, Poland, 2N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospekt 47, Moscow 111991, Russia, 3Center of Microbiology and Virology, Polish Academy of Sciences, Lodowa 106, 93-232 Łódź, Poland)
Abstract. Analysis by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy demonstrated that the O-specific polysaccharides of P. mirabilis PrK 42/57 and P. vulgaris PrK 43/57 are structurally similar to that of P. vulgaris PrK 44/57 and different from the polysaccharide of P. mirabilis PrK 41/57 studied earlier. The lipopolysaccharides of these strains were tested using enzyme immunosorbent assay, passive hemolysis and Western blot with O-antisera against P. mirabilis 42/57 and P. vulgaris 43/57 and 44/57, as well as with cross-absorbed O-antisera. The chemical and serological data revealed the basis for combining the four strains into Proteus serogroup O23 and division of this serogroup to three subgroups, one for P. vulgaris 43/57 and 44/57 and two others for P. mirabilis 41/57 and 42/57.
Keywords: Proteus mirabilis; lipopolysaccharide; O-specific polysaccharide; O-antigen; structure; serological reactivity.
Vol. 51, No. 2, 2003
CONTENTS
- When Antibodies are Antigens.
Felix Milgrom
Review
- How Endothelial Cell Organo-Specificity Mediates Circulating Cell Homing
Claudine Kieda (Centre de Biophysique Moléculaire, 45071 Orléans CEDEX 2, France)Abstract. Normal and transformed cells are homing from the circulation into tissues in a very selective way thanks to highly complex molecular mechanisms that govern cell-to-cell interactions and drive the homing of circulating cells to be achieved properly. Because this is characterised by a resulting high selectivity, it constitutes a template for targeted drug-, gene- or cell-therapy strategies. Designing a mimetic-based therapy requires the identification of the responsible selective molecules but also, their mechanisms of action and interactions with their ligands, together with their biological modulation and regulation. This homing/invasion event happens to be decisive at the level of the endothelium that lines the vessel walls. Since cell-to-cell interactions mean a double recognition process, this review will illustrate the part played by the endothelial cells (EC) and their adhesion molecules: the protein as well as the glycan part point of view, the chronology and environmental modulation of EC adhesion molecules expression. These characteristics should provide keys to understand the resulting overall specificity of cell localisation. Taking into account the cytokine microenvironment, it was recently documented a fundamental role for locally secreted chemokines which act through their restricted presentation by endothelial cells. As such, chemokines contribute to illustrate the concept of endothelial organo-specificity which is approached here uncovering the role of glycoconjugates signalling as the hallmark of refined cellular recognitions and discussed, in the context of potential drug design against site-directed diseases as metastases, inflammatory leukocytes recruitment, tumour/inflammation-induced angiogenesis…
Keywords: adhesion; chemokines; endothelial cell; lectins/glycoconjugates.
- Suppressors of Cytokine Signaling Proteins in Innate and Adaptive Immune Responses
Alexander Dalpke and Klaus Heeg (Institute of Medical Microbiology and Hygiene, Philipps-University, Marburg, Germany)Abstract. Suppressors of cytokine signaling (SOCS) proteins have been identified as important mediators of negative regulatory circuits within cytokine receptor signaling. They are induced upon stimulation by an increasing set of cytokines as well as further immunological stimuli and are capable to inhibit Janus-kinases and signal transducer and activator of transcription signaling. Inhibition is mediated by interfering directly with signal transduction at the receptor as well as targeting of associated molecules for proteosomal degradation. Targeted gene deletion approaches have revealed the importance of SOCS mediated termination of cytokine signaling during normal cellular activation. In addition to their function as classical feedback inhibitors SOCS proteins display a broad panel of inhibitory activity thereby mediating cross-talk modulation between different stimuli. The consequences for regulation of innate and adaptive immune responses are thus obvious. Finally, there are emerging data showing involvement of SOCS proteins in various immune diseases. Modulating SOCS activity could be a promising new approach for molecular therapeutic strategies.
Keywords: cytokine receptor signaling, immune system, inhibition, suppressors of cytokine signaling (SOCS)
- From Inflammation to Sickness: Historical Perspective
Barbara Plytycz1 and Rolf Seljelid2 (1Department of Evolutionary Immunobiology, Institute of Zoology, Jagiellonian University, R. Ingardena 6, 30-060Kraków, Poland, 2 Institute of Medical Biology, University of Tromso, Norway)Abstract. The concept of four cardinal signs of acute inflammation comes from antiquity as rubor et tumor cum calore et dolore, extended later by functio laesa (redness and swelling with heat and pain, extended later by loss of function). The contemporary understanding of this process we owe to nineteen-century milestone discoveries by Rudof Virchow, Julius Cohnheim, and Elie Metchnikoff. In twentieth century, the development of potent technological tools allowed the rapid expansion of knowledge of cells and mediators of inflammatory processes, and molecular mechanisms of their interactions. It turned out that some mediators of inflammation have both local and distant targets, among them the liver (responding by production of several acute phase reactants) and neurohormonal centres. In the last decades it has become clear that the immune system shares mediators and their receptors with the neurohormonal system of the body; thus they form a common homeostatic entity. Such an integrative view, introduced by J.Edwin Blalock, when combined with Hans Selye’s concept of stress, led to the contemporary understanding of sickness behaviour, defined by Robert Dantzer as a highly organised strategy of the organism to fight infections and to respond to other environmental stressors.
Keywords: local inflammatory response; acute phase response; sickness behaviour; immune-neuroendocrine network.
- The Dynamic and Complex Role of Mast Cells in Allergic Disease
Marianna Kulka and A. Dean Befus (Pulmonary Research Group, 550A HMRC, University of Alberta, Edmonton, Alberta, T6G 2S2, Canada)Abstract. Mast cells (MC) are found widely distributed in tissues and contribute to regulation of inflammatory responses and ongoing modulation of the tissues. Although MC are important in a variety of processes including innate immunity, their role in allergic disease has received increasing attention in the past decade. MC are located throughout the human body and upon allergen exposure they are stimulated via the IgE receptor (FceRI) to release several proinflammatory mediators such as tumor necrosis factor (TNF), reactive oxygen species such as nitric oxide (NO), proteases, and lipid-derived mediators. However, we now recognize that MC can be activated by a variety of mechanisms and that mediator release is a consequence of several intra- and extracellular signals. Some of these mechanisms, such as Fc receptor aggregation and proteinase activated receptor (PAR)-mediated activation facilitate and augment local inflammatory responses. Other mechanisms, such as interferon gamma (IFN-gamma) induction of nitric oxide (NO) may inhibit MC function and downregulate inflammatory responses. Increased understanding of these complex pathways has encouraged the development of therapies for allergic inflammation that target specific MC functions and mediators. Some novel strategies include oligonucleotides that induce or inhibit the production of specific mediators. Such approaches may yield useful therapies for allergic individuals in the near future.
Keywords: mast cells; allergy; IgE; proteases; cytokines.
- NK T Cell-NK Cell Cross-Talk: Reciprocal Interaction and Activation?
Johnna Wesley and Laurent Brossay (Department of Molecular Microbiology and Immunology and Graduate Program in Pathobiology, Division of Biology and Medicine, Brown University, Providence, RI 02912, USA)Abstract. Initiation and propagation of the immune response is the result of a series of coordinated cellular and biochemical interactions that lead to the activation of multiple cell types. It is now clear that an optimal immune response requires a precise and rapid communication between different cell subsets. This phenomenon, referred to as cross-talk, is believed to be an essential component of the immune response that provides necessary inflammatory mediators and cytolytic activity for controlling infections and diseases. An example of an effective cooperation between different cell types has been recently illustrated by the finding that specific activation of CD1 restricted natural killer T cells (NK T) can quickly lead to the activation of other subsets of cells such as natural killer (NK) and CD8 T cells.
Keywords: T cells cross-talk, NK cells, NK T cells, NK activation.
Immunogenetic
- Distribution of HLA-C Alleles Determined by PCR-SSP in Population of Low Silesia
Magdalena Prussak, Maria Mańczak, Bogusława Pochroń, Izabela Nowak and Piotr Kuśnierczyk (Laboratory of Immunogenetics, Department of Clinical Immunology, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland)Abstract. We typed 100 unrelated healthy Poles from Low Silesia region for HLA-C using low resolution PCR-SSP and compared observed allele frequencies with data published for other human populations. Poles appeared to be most similar to Germans and Englishmen, and were more distant from French, Catalans and Basques and dissimilar to non-Caucasoids from Equatorial Guinea and Japan. It would be interesting to HLA-C-type other Slavian and non-Slavian people from Middle and Eastern Europe for comparison.
Keywords: HLA-C, allele distribution, PCR-SSP typing, Low Silesian Polish population.
Infectious Immunology
- Serological Differentiation of H. pylori CagA(+) and CagA(-) Infections
Magdalena Chmiela1, Monika Wiśniewska1, Leokadia Bąk-Romaniszyn2, Tomasz Rechciński3, Izabela Płaneta-Małecka2, Władysław Bielański4, Stanisław J. Konturek4, Małgorzata Płonka4, Magdalena Klink5 and Wiesława Rudnicka1 (1Department of Immunology and Infectious Biology, University of Łódź, Banacha 12/16, 90-237 Łódź, Poland, 2Mother and Child Health Center, Rzgowska 281/289, 93-338 Łódź, Poland, 3Dr W. Biegański’s Hospital, Medical University, Kniaziewicza 1/5, 91-347 Łódź, Poland, 4Department of Physiology, Medical Academy, Jagiellonian University, Grzegórzecka 16, 31-532 Kraków, Poland, 5Microbiology and Virology Centre, Polish Academy of Sciences, Lodowa 106, 93-232 Łódź, Poland)
Abstract. Many of H. pylori strains causing gastroduodenal diseases have a cagA gene encoding CagA protein, a virulence factor of these bacteria. Anti-CagA antibodies produced by majority of people infected with CagA(+) strains can indicate such infection. In this study the efficacy of three immunoenzymatic tests: immunoblot (Milenia ID Blot H. pylori IgG, DPC Biermann GmbH, Germany) (MB) and ELISA, conducted with a recombinant immunodominant fragment of CagA (rCagA) and full length CagA molecule (flCagA), in detecting CagA(+) and CagA(-) infections, was compared. The 13C urea breath test (13C-UBT) was used for establishing H. pylori status. The serum samples from 157 individuals were used for serodiagnosis. The H. pylori CagA(+) infection was detected in H. pylori infected individuals with similar frequency by MB (64%) and flCagA-ELISA (60%) and little less frequently by rCagA-ELISA (53%). There was a high coincidence between the negative results of these three tests for H. pylori uninfected individuals with no anti-CagA IgG in the serum (96-100%). The results show that rCagA-ELISA and especially flCagA-ELISA are easy, inexpensive and useful noninvasive assays for discrimination of CagA(+) and CagA(-) H. pylori infections in the subjects examined by urea breath test.
Keywords: Helicobacter pylori, CagA, serodiagnosis.
Vol. 51, No. 3, 2003
CONTENTS
Review
- Immunomodulatory Effects of HMG-CoA Reductase Inhibitors
Farhad R. Danesh1, Ramon L. Anel1, Lixia Zeng1, Jon Lomasney2, Atul Sahai3 and Yashpal S. Kanwar2 (Departments of 1Medicine, 2Pathology and 3Pediatrics, The Feinberg School of Medicine of Northwestern University, Chicago, IL, USA)Abstract. 3-Hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitors or statins are competitive inhibitors of the rate limiting enzyme in cholesterol synthesis. Several clinical trials have shown a marked reduction in cholesterol levels associated with decreased cardiovascular mortality in patients treated with statins. However, more recent observations have suggested that the clinical benefits of statins may be, at least in part, independent of the effect of statins on cholesterol synthesis. These so-called pleiotropic or cholesterol-independent effects of statins could be the result of reduction in the formation of intermediaries in the mevalonate pathway as statins by inhibiting L-mevalonic acid synthesis also prevent the production of isoprenoids in the cholesterol biosynthetic pathway. Isoprenoids serve as important lipid attachments for the posttranslational modification of a variety of proteins such as small GTP-binding proteins of the Ras superfamily implicated in intracellular signaling. The list of different pleitropic effects of statins is still growing and include among others direct effects of statins on modulating endothelial function, decreasing oxidative stress, and more recently anti-inflammatory and immunomodulatory actions of statins. For instance, statins decrease T cell activation, the recruitment of inflammatory cells into atherosclerotic lesions, and inhibit IFN-gamma expression of MHCII on antigen-presenting cells. This review article summarizes the anti-inflammatory and immunomodulatory effects of statins and thus provides a new rationale to use statins as a new class of immunosuppressive agents.
Keywords: HMG-CoA reductase inhibitors; immunomodulation; transplantation; inflammation.
- Experimental Models of Inflammatory Bowel Disease
Antoni Stadnicki1 and Robert W. Colman2 (1Department of Internal Medicine, Medical University of Silesia, Katowice, Poland, 2Sol Sherry Thrombosis Research Center, Temple University, School of Medicine, Philadelphia, PA 19140, USA)Abstract. The etiology and pathogenesis of inflammatory bowel disease (IBD) remains unsolved but improved experimental models of enterocolitis have led to progress. Intestinal inflammation can be induced by chemical or dietary factors or by microbial products and experimental IBD. Many animal models of IBD can be used to evaluate new anti-inflammatory drugs. These models, however, usually demonstrate acute, self-limiting colitis. The spontaneous colitis models developed in the monkey, cotton-top tamarin, and C3H/HeJBir mouse mimic more features of human IBD. Inflammation is chronic and is under genetic control. The differential genetic susceptibility of inbred rat strains to chronic inflammation have been exploited. Lewis rats injected with bacterial products, peptidoglycan polysaccharide or indomethicin develop chronic relapsing enterocolitis, whereas closely related Buffalo or Fisher rat strains develop only transient inflammation and the specific inhibition of inflammatory mediators and target molecules have been tested. Over-expression (transgenic) or deletion (knockout) of specific genes have led to the development of rodent models of spontaneous colitis. Inflammation arises from a number of mutations of immunomodulatory molecules supporting the concept of genetic heterogeneity for IBD. The results obtained from experimental models have generated new hypotheses, expanded human studies, and suggested novel forms of therapy for IBD patients.
Keywords: experimental enterocolitis; kininogen; plasma kallikrein; intestinal inflammation; animal models.
- Wegener’s Granulomatosis – Autoimmunity to Neutrophil Proteinase 3
Ewa Wątorek, Maria Boratyńska and Marian Klinger (Department of Nephrology and Transplantation Medicine, Wrocław Medical University, Traugutta 57/59, 50-417 Wrocław, Poland)Abstract. Wegener’s granulomatosis is a small vessel vasculitis, associated with various clinical manifestations, among which the most common are respiratory tract disease and glomerulonephritis leading to renal failure. Pathogenesis of vascular injury in Wegener’s granulomatosis is ascribed to antineutrophil cytoplasmic antibodies directed (ANCA) mainly against proteinase 3, an enzyme from neutrophil granules. The reasons for breakdown of self-tolerance to proteinase 3 are unknown and together with molecular mechanisms underlying this immunoinflammation are the subject of research. Standard treatment of Wegener’s granulomatosis consists of cyclophosphamide and corticosteroids. In patients resistant to that therapy or with the refractory disease some alternative strategies involving tumor necrosis factor blocade, polyclonal antithymocyte globulin or monoclonal anti-T cell antibodies are applied.
Keywords: Wegener’s granulomatosis, ANCA, proteinase 3.
- CSF-1 as a Regulator of Macrophage Activation and Immune Responses
Matthew J. Sweet and David A. Hume (CRC for Chronic Inflammatory Diseases, Institute for Molecular Bioscience and Departments of Microbiology/Parasitology and Biochemistry, University of Queensland, Qld, 4072, Australia)Abstract. Macrophage activation is a key determinant of susceptibility and pathology in a variety of inflammatory diseases. The extent of macrophage activation is tightly regulated by a number of pro-inflammatory cytokines (e.g. IFN-gamma, IL-2, GM-CSF, IL-3) and anti-inflammatory cytokines (e.g. IL-4, IL-10, TGF-beta). Macrophage colony stimulating factor (CSF-1/M-CSF) is a key differentiation, growth and survival factor for monocytes/macrophages and osteoclasts. The role of this factor in regulating macrophage activation is often overlooked. This review will summarise our current understanding of the effects of CSF-1 on the activation state of mature macrophages and its role in regulating immune responses.
Keywords: CSF-1, macrophage, lipopolysaccharide, toll-like receptors, inflammation.
- Immunosuppressive Agents and Cytomegalovirus Infection
Kazuro Tanaka (Department of Infectious Diseases, Tokai University School of Medicine, Bohseidai, Isehara, Kanagawa 259-1193, Japan)Abstract. Cytomegalovirus (CMV) infection is the major infectious complication observed after organ transplantation. As rejection episodes always occur in allograft-transplanted recipients, various kinds of immunosuppressive agnets are used to control such rejection episodes. Among the commonly used immunosuppressive agents, anti-pan T cell monoclonal antibody (OKT3) is known to increase the risk of viral infections. A new immunological techniques have recently been developed to measure CMV-specific CD4 and CD8 cells by flowcytometry. Using the techniques, the high frequencies of specific CD4 and CD8 T cells have been shown to be required to survey the CMV (re)activation in the persistent/latent phase of CMV infection. An excessive T cell depletion by OKT would deplete such surveying T cells, thus resulting in the occurrence of CMV-associated diseases.
Keywords: cytomegalovirus; transplantation; immunosuppression; MHC/antigen-tetramer; virus-specific T cell.
Experimental and Clinical Immunology
- 17b-Estradiol Treatment Profoundly Down Regulates Gene Expression in Spinal Cord Tissue in Mice Protected from Experimental Autoimmune Encephalomyelitis
Agata Matejuk1,2,3, Jami Dwyer2, Corwyn Hopke1,2, Arthur A. Vandenbark1,2,4 and Halina Offner1,2 (1Department of Neurology, Oregon Health and Science University, Portland, OR 97201, USA, 2Neuroimmunology Research, Veterans Affairs Medical Center, Portland, OR 97239, USA, 3L. Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland, 4Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97201, USA)Abstract. It is now well documented that experimental autoimmune encephalomyeltitis (EAE) can be effectively prevented by estrogen therapy. Previously, we identified a limited set of genes that were altered in spleens of mice protected from EAE by 17b-estradiol (E2) treatment. As a continuation of these studies, we here present transcriptional changes in genes expressed in spinal cord tissue. The Affymetrix microarray system was used to screen more than 12,000 genes from E2-treated double Tg (BV8S2 and AV4) female mice protected from EAE vs. control mice with severe EAE. We found that estrogen therapy had a profound inhibitory effect on expression of many immune-related genes in spinal cords. Estrogen significantly affected transcription of 315 genes, 302 that were down-regulated and only 13 that were up-regulated by >2.4 fold. A number of genes encoding the histocompatibility complex, cytokines/receptors, chemokines, adhesion molecules, and signal transduction proteins, were strongly down regulated (>20 fold) in estrogen treated mice to levels similar to spinal cord tissue from unmanipulated mice. The identification of genes with altered expression patterns in spinal cords of estrogen treated mice provides unique insight into the process that ultimately results in protection against EAE.
Keywords: 17b estradiol; EAE; microarray; spinal cord.
- Diagnostic Value of Pancreatic Elastase-1 in Human Acute Pancreatitis
Urszula Wereszczyńska-Siemiątkowska1, Monika Jedynak2, Barbara Mroczko3 and Andrzej Siemiątkowski2 (1Department of Gastroenterology, 2Departmentt of Anaesthesiology and Intensive Therapy, 3Deparmtnet of Biochemical Diagnostics, Medical University, Białystok, Poland)Abstract. The diagnosis of acute pancreatitis is usually confirmed by a significant increase of the serum amylase and/or lipase level. However, serum pancreatic elastase–1 (pEla-1) was found to be a more sensitive diagnostic marker in acute pancreatitis (AP), when assayed by RIA procedure. We analysed the serum concentration of pancreatic elastase-1, measured by ELISA technique in 46 patients with acute pancreatitis and in the control group of 12 healthy volunteers. At admission (day 1) we found significantly higher pEla-1 level in patients with AP when compared to the control group. During the following days, the concentration of pEla-1 rapidly decreased nearly to undetectable value on the third day. There was no significant difference between patients with mild and severe AP and according to aetiology. We suggest that pEla-1 has a little diagnostic value and does not provide additional information to that of cheaper and more widely available serum amylase and lipase.
Keywords: acute pancreatitis, pancreatic elastase-1, diagnosis, prognosis.
Immunogenetics
- Lack of Association between Exon 1 CTLA-4 Gene Polymorphism A(49)G and Multiple Sclerosis in Polish Population of the Lower Silesia Region
Dorota Boćko1, Małgorzata Bilińska2, Tadeusz Dobosz3, Magdalena Żołędziewska3, Katarzyna Suwalska1, Anna Tutak1, Ewa Gruszka2 and Irena Frydecka1, 4 (1Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland, 2Department of Neurology, 3Department of Forensic Medicine, 4Department of Hematology, Medical University, Wrocław, Poland)
Abstract. Multiple sclerosis (MS) a chronic inflammatory demyelinating disease of the central nervous system (CNS) is believed to have a T-cell mediated autoimmune etiology. The cytotoxic T lymphocyte antigen 4 (CTLA-4) gene is a strong candidate for the involvement in autoimmune diseases because CTLA-4 plays an important role in downregulation of early and late stages of T cell activation and maintenance of peripheral T cell tolerance. To examine the genetic association of the CTLA-4 gene locus with MS, we analyzed exon 1 CTLA-4 gen polymorphism A(49)G in 102 unrelated Polish MS patients in Lower Silesia region and 101 age and sex matched healthy subjects. The distribution of CTLA-4 exon 1 A(49)G genotype, phenotype and allele frequencies did not differ between patients with MS and healthy subjects.
Keywords: CTLA-4; A(49)G; multiple sclerosis; Lower Silesia.
Vol. 51, No. 4, 2003
CONTENTS
Review
- Integrating B Cell Homeostasis and Selection with BLyS
Susan Harless Smith and Michael P. Cancro (Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA)Abstract. The mechanisms that maintain a pool of B cells that is adequately diverse yet devoid of pathogenic autoreactivity remain poorly understood. B cells complete maturation after migrating to the periphery, where they transit several intermediate developmental stages prior to recruitment into the long-lived primary pool. Since B lineage commitment is not coupled to peripheral B cell numbers and most mature peripheral B cells are quiescent, the sizes of mature peripheral compartments are primarily determined by the proportion of immature B cells that survive transit through later developmental stages, coupled with the longevity of mature B cells themselves. Compelling evidence indicates that the B cell antigen receptor (BcR) plays an essential role in all of these processes, but further findings indicate a similar role for the recently described tumor necrosis factor family member, B lymphocyte stimulator (BLyS). Signaling through the BLyS receptor, Bcmd/BR3, controls B cell numbers in two ways: by varying the proportion of cells that complete transitional B cell development, and by serving as the primary determinant of mature B cell longevity. The striking congruence of BcR- and BLyS-mediated effects on B cell selection and survival suggests these pathways may be related. The recent discovery that BcR signaling is selectively coupled to Bcmd/BR3 expression links BcR- and BLyS-mediated activities in transitional and mature B cells, suggesting specificity-based selection and survival may be mechanistically similar processes.
Keywords: B lymphocytes; BLyS; homeostasis; development.
- PPARg – an Important Regulator of Monocyte/Macrophage Function
Andreas von Knethen and Bernhard Brüne (Department of Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany)Abstract. Regulation of monocyte/macrophage function is important to coordinate immune responses. Their contact with invading pathogens activates signaling pathways that provoke pro-inflammatory gene expression and thus causing a locally restricted inflammation. Recently, the peroxisome proliferator activated receptorg (PPARg) has been identified to antagonize pro-inflammatory responses in monocytes/macrophages causing an anti-inflammatory and/or desensitized phenotype to predominate. For PPARg general mechanisms in facilitating the transition from a pro- to an anti-inflammatory phenotype have been elucidated. PPARg is a member of the nuclear receptor superfamily and activated upon endogenous as well as exogenous agonist binding. Here we focus on its role in monocyte/macrophage biology in affecting inflammation. Summarizing current information, a model is proposed, giving rise to potential new therapeutic possibilities for the treatment of diseases presumably involving PPARg-dependent regulatory circuits.
Keywords: inflammation; monocytes/macrophages.
- The Role of Autoimmunity in the Pathogenesis of Lung Allograft Rejection
David S. Wilkes (Departments of Medicine, Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202, USA)Abstract. For many patients, lung transplantation is the only definitive treatment modality for different forms of end stage lung disease. However, the lung is rejected more often than any other type of solid organ allografts, and the five year survival is less than that of other transplanted organs. While alloimmunity directed against donor transplantation antigens is believed to be the key mechanism that mediates rejection responses, newer immunosuppressive regimens designed to abrogate alloimmune activation have not improved survival. Accordingly, these data suggest that other antigens are involved in rejection. Autoimmune responses, reported to occur during allograft rejection, could participate in graft destruction. This review article discusses the role of autoimmune responses to type V collagen ([col(V)], a minor collagen in the lung, in the pathogenesis of lung allograft rejection. By recognizing that lung transplant rejection involves both alloimmune and autoimmune responses, scientific investigation may uncover novel targets for therapeutic intervention that could prolong the life of the lung transplant recipient.
Keywords: lung transplantation; alloimmune response; autoimmune response; transplant rejection.
- Are NKT Cells Essential for Endotoxic Shock?
Masashi Emoto (Department of Immunology, Max-Planck-Institute for Infection Biology, Berlin, Germany)Abstract. Endotoxic shock is a major health threat caused by Gram-negative bacteria and their unique cell wall component, lipopolysaccharide which induces exaggerated production of proinflammatory cytokines? Although macrophages play a central role in the pathogenesis of endotoxic shock, NK1+ cells are also involved in this mechanism. NK1+ cells comprise two major populations, namely NK cells and NKT cells. It remains, however, elusive whether either NK cells, NKT cells or both are involved in induction of endotoxic shock. This review will focus on the relative contribution of these NK1+ cells to the pathogenesis of endotoxic shock.
Keywords: endotoxin shock, NK cell, NKT cell, IFN-g, lipopolysaccharide.
- Phage Therapy: a Reappraisal of Bacteriophages as Antibiotics
Jameel M. Inal (University Hospital Basel, Department of Research, Basel, Switzerland)Abstract. The concept of phage therapy to treat bacterial infections was born with the discovery of bacteriophage almost a century ago. After a chequered history its current renaissance is fuelled by the dangerous appearance of antibiotic-resistant bacteria on a global scale. As a mark of this renewed interest, the unanswered problems of phage therapy are now being addressed, especially for human use. Phage therapy in agricultural, food processing and fish farming industries is already successful and this review, whilst being aware of the potential drawbacks, emphasizes the need for further carefully controlled empirical data on its efficacy and safety in treating human and animal disease, especially in view of its numerous advantages over antibiotics. Finally the potential of phage therapy against bioterrorism and the emergence of second generation phage antibacterials based on phage-derived single-protein lysis systems are addressed.
Keywords: phage therapy; bacteriophage; antibiotic resistance.
- Considerations on Clinical Use of T Cell Immunotherapy for Cancer
Gregory E. Plautz, Peter A. Cohen and Suyu Shu (Center for Surgery Research, The Cleveland Clinic Foundation, Cleveland, OH 44195, USA)Abstract. The recognition by effector T lymphocytes of novel antigenic targets on tumor cells is the premise of specific targeted immunotherapy of cancer. With the molecular characterization of peptide epitopes from melanoma antigens, and more recently broadly expressed tumor antigens, there has been considerable enthusiasm for clinical evaluation of peptide tumor vaccines. Immunologic monitoring of vaccinated patients has demonstrated expansion of CD8+ T cells that react with the relevant peptide and, more importantly, with native tumor. In most instances however, vaccine-induced CD8+ T cell responses alone have not been sufficiently robust or sustained to translate into a high percentage of durable clinical responses. Vaccine strategies have also utilized dendritic cells (DCs) that have been modified to present tumor antigens. The superior antigen processing capacity and co-stimulatory function of DC convey a powerful stimulatory signal to both CD4+ and CD8+ T cells. Several strategies are attempting to broaden the immune response beyond single antigens by introducing the entire complement of tumor antigens into DCs. Adoptive immunotherapy is a promising strategy to recover tumor-reactive precursor T cells from patients, stimulate them to induce numerical expansion, and then re-infuse them. Ex vivo manipulation of the tumor-reactive T cells also permits cytotoxic therapy to be administered to the patient without damaging the effector cells. Recently, host lymphodepletion prior to adoptive transfer of effector T cells has resulted in an extremely high and sustained frequency of effectors that has achieved therapeutic efficacy against bulky metastatic disease in a substantial fraction of treated patients.
Keywords: tumor antigens, T lymphocyte, immunotherapy, dendritic cell.
Experimental and Clinical Immunology
- Time-Dependent Observations of Secretion Marker Levels in Nasal Secretion after Histamine and Methacholine Provocations
Małgorzata Pupek1, Wojciech Mikulewicz2, Jarosław Mielnik2,3, Bożena Batycka2 and Iwona Kątnik-Prastowska1 (1Department of Chemistry and Immunochemistry, Wrocław Medical University, Bujwida 44a, 50-345 Wrocław, Poland, 2Otolaryngology Department, Regional Hospital of Wrocław, Kamieńskiego 73a, 51-124 Wrocław, Poland, 3Department of Basic Medical Sciences, Wrocław Medical University, Kochanowskiego 14, 51-601 Wrocław, Poland)Abstract. Nasal provocation tests with histamine and methacholine were carried out in 25 healthy men on an effort to assess the dynamic changes of albumin, total IgA, secretory IgA and lactoferrin concentrations in the nasal secretion. The trials were performed with 0.5, 1, and 4 mg of histamine and 8, 16, 32 mg of methacholine. Each dose of histamine or methacholine was sprayed into a nose every second day, and with two days interval between two provocating agents. The nasal secretions were collected after saline spraying only forming baseline group and after 3, 10 and 15 minutes of the challenge agent administration. The baseline levels presented the following values: for albumin 257± 230 µg/ml, secretory IgA 608 ± 379 µg/ml, total IgA 1025 ± 423 µg/ml, and lactoferrin 213 ± 156 µg/ml. The increase of albumin level after nasal provocation, particularly significant after histamine administration (to 3713 ± 2311 µg/ml), indicates the incessant protein plasma leaking from the blood circulation to the nasal secretion. After administration of both provocating agents there was the significant gradual decrease of secretory IgA level, even below the baseline value. After the 2nd and the 3rd doses of methacholine and histamine spraying the concentration of secretory IgA decreased 2-3 times and was found to be 200-300 µg/ml, respectively. Also, lactoferrin concentration values decreased gradually after the 2nd and 3rd doses of methacholine and histamine to level close the baseline value. These observations suggest time and dose dependent, a non-specific dysfunction of local immunity response after nasal provocations.
Keywords: nasal challange, nasal secretion markers, lactoferrin, IgA, secretory IgA.
- Effect of Exogenous Opioid Peptides on TNF-a-induced Human Neutrophil Apoptosis in Vitro
Zofia Sułowska1, Ewa Majewska2, Henryk Tchórzewski1, 3 and Magdalena Klink1 (1Microbiology and Virology Center, Polish Academy of Sciences, Łódź, Poland, 2Department of Pathophysiology and Clinical Immunology, Medical University Łódź, Poland, 3Department of Clinical Immunology, Polish Mother`s Memorial Institute, Łódź, Poland)
Abstract. Polymorphonuclear leukocytes (neutrophils) apoptosis is an important mechanism regulating the life span and some functions of neutrophils at inflamed sites. The opioid peptides are present in the peripheral circulation and their concentrations rapidly increase as the result of stress and inflammation. The effect of opioid peptides such as met-enkephalin (M-ENK) and beta-endorphin (b-END) on tumor necrosis factor a (TNF-a)-induced apoptosis in human neutrophils in vitro was investigated. Neutrophils isolated from peripheral blood were cultured in the absence or presence of 10-6-1010 M of opioid peptides for 8, 12 and 18 hours. Features of apoptotic neutrophils were measured by flow cytometric method based on analysis of apoptotic nuclei (DNA content). We found that M-ENK and b-END enhanced both non-induced and TNF-a-induced neutrophil apoptosis in vitro in a dose-dependent manner. The effect of opioid peptides on modulation of neutrophil apoptosis was not reversed by opioid-receptor antagonist naloxone. The results suggest that M-ENK and b-END can regulate neutrophil life span via apoptosis and in this way may participate in resolution of inflammation.
Keywords: apoptosis, opioid peptides, human polymorphonuclear leukocytes (neutrophils), flow cytometry, TNF-a.
Vol. 51, No. 5, 2003
CONTENTS
Review
- The Role of Hepatocyte Growth Factor/c-met Interactions in the Immune System
Grzegorz Skibinski (Respiratory Research Group, Department of Clinical Biochemistry, Institute of Clinical Science, Queen’s University of Belfast, Belfast BT12 6BJ, Northern Ireland, UK)Abstract. Hepatocyte growth factor (HGF) is a pleiotropic cytokine with mitogenic, motogenic and morphogenic activity for mainly epithelial and endothelial target cells. All the different effects of HGF are mediated through its specific receptor met, a heterodimeric transmembrane tyrosine kinase. The broad activity of HGF and its impact on many physiologic and pathologic processes are reflected by met expression in a variety of organs and cell types. This paper discusses expression of HGF and c-met within the immune system and their interactions in the control of immune cell functions.
Keywords: hepatocyte growth factor; c-met; immune system cell functions
- Processes Involved in the Repair of Injured Airway Epithelia
Yohannes Tesfaigzi (Lovelace Respiratory Research Institute, Albuquerque, NM 87108, USA)Abstract. Recent studies have uncovered many aspects of the repair processes that follow airway epithelial injury. Although the repair process has common elements among various epithelia, such as the ones lining the airways, skin, and gut, there are differences based on their diverse functions. Whenever possible, similarities are pointed out that could help researchers further investigate their application to airway epithelia, although it would be beyond the scope of this review to cover the processes that may occur during the repair of all types of epithelia. In general, five major steps are involved in the recovery of airway epithelia from injury: 1) epithelial cells migrate to cover denuded areas within minutes, and certain proteins, such as the trefoil factor family proteins, are crucial to this process; 2) epithelial cells start to proliferate in order to replace injured cells and to differentiate to establish squamous or mucous cell metaplasia; 3) because more epithelial cells are present after proliferation, some of the cells must be discarded to restore the epithelium to the original condition; 4) once the cell numbers have been reduced to those found in unexposed individuals, the normal proportions of cell types are restored; 5) finally, studies from exposures of rats to ozone show that epithelial cells can adapt and develop a memory of the chronic exposure to which they were exposed. This adaptation allows the epithelium to respond quickly, thus minimizing further injury. Although the molecular mechanisms involved in these major steps of the recovery process are largely unknown, disruption of these steps clearly causes the permanent changes observed in diseases such as asthma, chronic bronchitis, and cancer; therefore, extensive research in these areas may provide ideas for novel therapies.
Keywords: epithelium, proliferation, cell cycle, apoptosis, differentiation, homeostasis.
- The Immunology of Chlamydia trachomatis
Bożena Zdrodowska-Stefanow (Department of Dermatology and Venerology, Medical University, Białystok, Poland), Iwona Ostaszewska-Puchalska and Katarzyna Puciło (Center for STD Research and Diagnostisc, Białystok, Poland)Abstract. Chlamydia trachomatis (C. tachomatis) is one of the most common sexually transmitted bacterial agents. What distinguishes it from other organisms is its intracellular reproductive cycle. Up to now, four antigens have been identified in the Chlamydia genus: genus-specific antigen as well as species-specific, type-specific and subspecies-specific. C. trachomatis is a powerful immunogen which stimulates the host’s immunological processes. The intracellular parasitism of the bacteria is the basis for both symptomatic or asymptomatic infection as well as for chronic ones. The primary infection leads to a local inflammatory reaction due to penetration and reproduction of the bacteria in the epithelial cells and to IgA secretory antibody production. In most cases the host’s reaction to the primary infection is transient and does not cause tissue damage. In the course of chronic infection or reinfection, the most important processes are those of delayed hypersensitivity, which lead to a fast and intense immunological reaction of specifically sensitized Th1 lymphocytes. This reaction leads to progressive damage of the epithelial cells and to cicatrization and fibrosis, which means irreversible complications. Interferon gamma is of special importance in the process of C. trachomatis infection. High concentrations of it inhibit the bacteria’s reproductive cycle, while lower concentrations promote the development of atypical, non-contagious forms of Chlamydia of diminished metabolic activity and altered antigenicity. The chlamydial heat shock proteins are considered to be of great importance lately. Their molecular weights of 60 and 10 kDa are a powerful stimulant of immunological reactions and show significant homology (40-90%) to human and other bacterial heat shock proteins.
Keywords: Chlamydia trachomatis, primary infection, latency, reifection.
- Viruses as Hijackers of PML Nuclear Bodies
Andreas Möller and M. Lienhard Schmitz (Department of Chemistry and Biochemistry, University of Bern, CH-3012 Bern, Switzerland)Abstract. Promyelocytic leukemia nuclear bodies (PML-NBs) are discrete interchromosomal macromolecular structures. The integrity of this dynamic nuclear subcompartment critically depends on the presence of the name-giving PML protein. Among the permanent or transient residents of PML-NBs are various regulatory proteins, including Sp100, CBP, pRb, HIPK2, RAD51 and p53. PML-NBs are frequently targeted by viral infections, as a number of different RNA and DNA viruses including herpesviruses, adenoviruses, papovaviruses, papillomaviruses and arenaviruses cause changes in PML-NBs. Viruses interfere with PML-NB in two ways: 1) some viral proteins can associate with PML-NB proteins and/or lead to the destruction and lysis of this subnuclear compartment, thus aiding viral gene expression and disabling the host’s innate immunity; 2) the parental genomes of some nuclear-replicating DNA viruses associate preferentially with PML-NBs, which presumably serves to assist in viral gene expression or replication. Here we feature the different viral strategies leading to the hijacking of PML-NBs and discuss the consequences for the immune response.
Keywords: promyelocytic leukemia (PML), PML nuclear bodies, virus infection, SUMO, nuclear bodies.
- Quantitative Real-Time PCR in Cancer Research
Simone Mocellin, Carlo R. Rossi (Surgery Branch, Department of Oncological and Surgical Sciences, University of Padova, Italy) and Francesco M. Marincola (Immunogenetics Laboratory, Department of Transfusion Medicine, Clinical Center, National Institutes of Health, Bethesda, MD, USA)Abstract. In the era of the Human Genome Project, quantitation of gene expression by tumor/host cells is of paramount importance to investigate gene patterns responsible for cancer development, progression and response/resistance to treatment. Quantitative real-time PCR (qrt-PCR) technology has recently reached a level of sensitivity, accuracy and practical ease that support its use as a routine bioinstrumentation for gene level measurement. Several applications have been already implemented in the field of cancer research, and others are being validated, showing that this molecular biology tool can provide both researchers and clinicians with precious information concerning the behaviour of tumors. The knowledge of the biochemical principles underlying this biotechnology can be of great value to correctly interpret qrt-PCR data.
Keywords: quantitative PCR, cancer research.
- Using Knockout Mice to Study Experimental Meningitis
Robert Paul, Uwe Koedel and Hans-Walter Pfister (Department of Neurology, Klinikum Grosshadern, Ludwig-Maximilians-University Munich, Germany)Abstract. Despite the use of antibiotics, the prognosis of bacterial meningitis is still poor due to central nervous system (CNS) complications, such as brain edema formation, cerebrovascular alterations, and intracranial hemorrhage. Experimental studies with animal models have given new insights into its pathophysiology during the acute phase of the disease. In recent years, genetically engineered mice have become a powerful tool in investigating the role of particular genes by targeted deletion and have also been applied in bacterial meningitis research. By using knockout mice, new knowledge of the roles of the different cytokines, proteases, and oxidants involved in the inflammatory cascade has emerged. In the future, temporal and cell type-specific control of gene expression will provide even more information on the impact of a particular gene on meningitis-induced brain damage.
Keywords: bacterial meningitis; animal model; knockout mice; inflammation; CNS.
Experimental and Clinical Immunology
- The Effect of Short-Term and Chronic Glucocorticoid Therapy on Lymphocyte Glucocorticoid Receptor Number in Patients with Asthma
Alicja Grzanka and Barbara Rogala (Chair and Clinical Department of Internal Diseases, Allergology and Clinical Immunology Medical University of Silesia, Katowice, Poland)Abstract. Glucocorticoid (GCs) hormones are widely used in the treatment of bronchial asthma. However, not all aspects of their pharmacological effects are well understood as yet. It is know that the effects of GCs are mediated through GC receptors (GCRs). We sought to evaluate the effect of short-term and chronic GC therapy on GCR number in peripheral blood lymphocytes, the relationship between GCR number and cortisol concentrations in asthma patients treated with GCs as well as the response to GC therapy in various pictures of this disease. Sixty-nine patients with bronchial asthma were investigated. Thirty-five of them had received steroid therapy: 18 patients for 1 to 15 years and 17 patients for 13 days after a prior 3 month discontinuation of steroid treatment. The control group consisted of 28 healthy, age matched volunteers. GCR numbers were determined using tritriated dexamethasone as a ligand. The scatchard method was applied to calculate the maximal specific binding and the dissociation constant. The number of receptor sites per lymphocyte was calculated. Cortisol was measured by radioimmunoassay. Lymphocyte GCR numbers in patients with bronchial asthma who were not treated with steroids, did not differ from age-matched healthy persons (means 8115±812 and 7905±832). A significant decrease in receptor number was seen in patients receiving steroid therapy (mean 4331±1041). There was also a significant difference in receptor number between the groups with short-course (mean 3741±549) and chronic steroid therapy (mean 4885±1095). The number of GCRs did not correlate with age, sex, clinical state or serum cortisol concentration in either group.
Keywords: bronchial asthma, glucocorticoid therapy, glucocorticoid receptor.
- CD30 Expression on Allergen- and Non-Allergen-Specific T Cell Lines and Its Role in Cytokine Production
Maciej Tarkowski (Department of Immunotoxicology, Institute of Occupational Medicine, Łódź, Poland)
Abstract. The main interest in CD30 has mainly focused on its ability to discriminate between T helper (Th)2 and Th1 subpopulations. The role of CD30 as the marker for Th2 cells is still controversial, which may be due to the fact that the expression and the role of CD30 is not fully understood. The data presented in this paper provides information on the expression and activity of CD30 in T cell lines specific to allergen or tuberculin-purified protein derivative (PPD) as the model of Th2 or Th1 responses, respectively. The results have shown that CD30 expression was the highest on T cells stimulated with antigen in the presence of interleukin (IL)-12 and it was present on both cell lines, regardless of antigen specificity. Activation of the CD30 receptor on CD4+ T cells, however, showed differences in mRNA expression for IL-4 between these cells. IL-4 mRNA was induced by CD30 costimulation at the same level as was obtained with anti-CD28 agonistic antibodies in allergen-specific T cells. In PPD-specific T cells this effect was not observed. Additionally, there was no effect of anti-CD30 stimulation on IL-6 mRNA expression in any of the cell lines. Comparison of protein cytokine levels for IL-4 and interferon (IFN)-gamma have shown that the highest production of IL-4 was obtained from allergen-specific T cells costimulated with anti-CD28. Although this effect was much lower in the case of CD30 costimulation, it was still above that the anti-CD3 activation alone. No effect of CD30 activation was observed in regard of IFN-gamma mRNA or protein expression in any cell line. The results of the study showed that CD30 receptor is not exclusively present on Th2 cells; however its activity may promote a Th2-dependent reaction by modulating IL-4 production.
Keywords: CD30, T cells, Th1, Th2.
Vol. 51, No. 6, 2003
CONTENTS
Review
- Cytokine Signaling/Transcription Factor Cross-Talk in T Cell Activation and Th1-Th2 Differentiation
Ana C. Liberman, Damian Refojo and Eduardo Arzt (Laboratory of Physiology and Molecular Biology, Department of Physiology and Cellular and Molecular Biology, Buenos Aires University, Buenos Aires, Argentina)Abstract. The secretion of interleukin (IL)-2 is a key event in T cell activation. IL-2 allows T cells to enter into the S phase of the cell cycle and divide. After the activation phase takes place, T lymphocytes proliferate and differentiate to generate effector T cells. Thereby, T helper (Th) precursor cells, which are functionally immature, may become Th1 or Th2 effector cells. These subsets are responsible for cell-mediated immunity and humoral responses, respectively. Both, T cell activation and Th differentiation are processes that depend on changes in the pattern of gene expression. The expression and changes in the genes responsible for these events are regulated by transcription factors. This review will focus on both transcription factors involved in the control of IL-2, as well as those that are key in T helper differentiation.
Keywords: T cell differentiation; T cell activation; TCR; IL-2; GATA-3; T-bet.
- Viral Strategies in Modulation of NF-kB Activity
Katarzyna Lisowska and Jacek M.Witkowski (Department of Pathophysiology, Medical University of Gdańsk, Poland)Abstract. Activation of nuclear factor (NF)-kB transcription factors family in response to different stimuli such as inflammatory cytokines, stress inducers or pathogens’ products results in host innate and adaptive immunity. NF-kB plays a central role in promoting the expression of genes involved in inflammatory, immune and apoptotic processes, including those encoding cytokines, chemokines, cytokine receptors or proteins involved in antigen presentation. Although the main function of NF-kB is to activate specific genes in the cells of the immune system, its role in controlling the host cell cycle makes NF-kB an interesting target for pathogenic viruses. Some viruses take advantage of anti-apoptotic properties of NF-kB to escape host defence mechanisms, other use apoptosis to spread. This review describes the role of NF-kB family in immune responses, mechanism of NF-kB activation and different strategies that viruses have developed to modulate NFkB pathway in order to facilitate and enhance viral replication and avoid host immune responses.
Keywords: NF-kB, IKK complex, viral infection, apoptosis.
- The Immunological Synapse
Thomas Klemmensen, Lars Ostergaard Pedersen (Department of Molecular Pharmacology, Lundbeck A/S) and Carsten Geisler (Institute of Medical Microbiology and Immunology, University of Copenhagen, The Panum Institute, Blegdamsvej 3, DK-2200 Copenhagen, Denmark)Abstract. Induction of a proper adaptive immune response is dependent on correct transfer of informations between antigen-presenting cells (APCs) and antigen specific T cells. Defects in information transfer may result in development of diseases, e.g. immunodeficiencies and autoimmunity. A distinct 3-dimensional supramolecular structure at the T cell/APC interface has been suggested to be involved in the information transfer. Due to its functional analogy to the neuronal synapse, the structure was termed the “immunological synapse” (IS). Here, we review molecular aspects concerning IS formation, appearance, and cessation. In addition, proposed functions of the IS are discussed. The process of IS formation occur in a sequential manner initially causing a remarkable large-scale redistribution of a number of integral membrane- and cytosolic proteins. At the T cell/APC interface the structure comprises in its nascent stage a non-random pattern of protein distribution. The protein pattern is regulated during development of the mature IS and is finally organized into concentric rings of co-receptors and adhesive molecules surrounding the T cell antigen receptor (TCR). The relocations of proteins are influenced by passive as well as active mechanisms. Considering the IS as a device enabling cell-cell communication, clarification of its exact function is of huge general as well as therapeutic interest.
Keywords: immunological synapse, signaling, T cell, TCR, MHC.
- Dynamic Control of B Lymphocyte Development in the Bursa of Fabricius
Phillip E. Funk and Jessica L. Palmer (Department of Biological Sciences, DePaul University, Chicago, IL 60614, USA)Abstract. The chicken is a foundational model for immunology research and continues to be a valuable animal for insights into immune function. In particular, the bursa of Fabricius can provide a useful experimental model of the development of B lymphocytes. Furthermore, an understanding of avian immunity has direct practical application since chickens are a vital food source. Recent work has revealed some of the molecular interactions necessary to allow proper repertoire diversification in the bursa while enforcing quality control of the lymphocytes produced, ensuring that functional cells without self-reactive Ig receptors populate the peripheral immune organs. Our laboratory has focused on the function of chB6, a novel molecule capable of inducing rapid apoptosis in bursal B cells. Our recent work on chB6 will be presented and placed in the context of other recent studies of B cell development in the bursa.
Keywords: bursa of Fabricius, B lymphocytes, apoptosis, intracellular signaling.
- New Insights into the Pathophysiology and in Vivo Function of IgG Fc Receptors through Gene Deletion Studies
Ulrich Baumann, Reinhold E. Schmidt and J. Engelbert Gessner (Department of Clinical Immunology, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hanover, Germany)Abstract. Fc-receptors for IgG (FcgRs) are critically involved at multiple stages of an immune response, ranging from antigen presentation and regulation of antibody production to the end-stage effector mechanisms of inflammation. Immunolglobulin G autoantibodies that are detectable in the majority of autoimmune diseases are ligands for FcgRs. The three classes, FcgRI, FcgRII, and FcgRIII, vary in their antibody affinity, cellular expression and in vivo function. We review the current knowledge on regulation and diverse functions of the distinct FcgRs and describe the evidence of their important immunoregulatory roles in autoimmunity based on recent work in animal models.
Keywords: IgG Fc receptors, gene deletion, autoimmunity.
- Development and Selection of T Cells: How Many Subsets? How Many Rules?
Paweł Kisielow (Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wrocław, Poland)Abstract. Since the discovery indicating that thymus derived lymphocytes (T cells) can be divided into two subpopulations: CD8+ (killer) and CD4+ (helper) cells, subsequent studies revealed bewildering heterogeneity of T cells. In the present review an attempt is made to present the actual picture of T cell heterogeneity, introduce some order into nomenclature and summarize the rules behind the development and selection of different, currently recognized T cell subsets.
Keywords: thymus, T cell development, T cell heterogeneity, positive selection, negative selection, T cell subsets.
Experimental and Clinical Immunology
- Efficacy of Procalcitonin Measurement in Patients after Total Thyroidectomy Due to Medullary Thyroid Carcinoma
Paweł Bolko, Ewa Manuszewska-Jopek, Krzysztof Michałek, Ryszard Waśko, Magdalena Jaskuła and Jerzy Sowiński (Department of Endocrinology, Metabolism and Internal Diseases, Karol Marcinkowski University of Medical Sciences, Poznań, Poland)Abstract. Procalcitonin (PCT) is a protein synthesised by the thyroid C-cells, inside which is cut into calcitonin (CT) and catacalcin. It remains undetectable in serum in normal conditions. Its level increases during inflammation and in small-cell lung cancer. There have been studies suggesting that the PCT level increases in medullary thyroid carcinoma (MTC). So far there have been no reports that would assess the usefulness of PCT detection in MTC. Our aim was to evaluate the usefulness of serum PCT assays in the patients with MTC. We investigated 24 patients at the age of 17-78 years, all after a total thyroidectomy due to MTC. All patients had serum CT concentrations measured with the radioimmune assay (RIA-DPC). The upper limit of CT level was 60 pg/ml. The serum PCT was evaluated with immunochromatographic kit . The reaction was considered positive when PCT level exceeded 0.5 ng/ml. In all cases the C-reactive protein serum level was measured. The statistical analysis was performed with the Statistica 5.1G. The CT levels in all patients varied from 0 to 1410, mean 603.8 pg/ml. In 8 patients the CT level was within normal range, in 6 patients it was marginally and in 10 patients markedly elevated. The PCT test was considered positive in 16 patients. There was correlation between serum PCT and CT concentrations (Spearman test, p<0.0001). The PCT levels varied considerably between patients with normal, marginally and markedly elevated CT levels (Kruskal-Wallis test, p=0.0013). All patients had normal CRP values. Fisher’s exact test revealed a correlation between serum PCT and CT increase (p=0.04). Further studies of a bigger group of patients should be considered, so far, the PCT assay can be thought useful in cases of unclear CT concentration.
Keywords: medullary thyroid carcinoma, procalcitonin, calcitonin, follow-up.
- CD80 and CD86 Expression on LPS-Stimulated Monocytes and Effect of CD80 and CD86 Blockade on IL-4 and IFN-g Production in Nonatopic Bronchial Asthma
Ryszard Rutkowski1, Tadeusz Moniuszko2, Anna Stasiak-Barmuta1, Bożena Kosztyła-Hojna3, Marek Alifier4, Krzysztof Rutkowski5 and Anetta Tatarczuk-Krawiel6 (1Department of Pediatric Allergology, 2Department of Allergology and Internal Medicine, 3Department of Otolaryngology, 4Department of Neonatology Medical University, 5Student of Medical University, 6GlaxoSmithKline, Białystok, Poland)
Abstract. CD80 and CD86 seem to play an important role in the allergen induced secretion of IL-5 and IL-13. Up till now, the expression of CD80 (B7.1) and CD86 (B7.2) on monocytes and kinetics of these molecules expression on lipopolysaccharide–stimulated monocytes in nonatopic asthma have not been defined. Using monoclonal antibodies we have compared the expression of CD80 (B7.1) and CD86 (B7.2) on monocytes of healthy persons and nonatopic asthmatic patients. We have also assessed the effect of CD80 and CD86 inactivation on interleukin (IL)-4 and interferon gamma (IFN-g production in nonatopic asthmatics and healthy subjects. We found that low expression of CD80 on studied monocytes (1.64±0.65 vs. 3.53±1.43%) and moderate expression of CD86 (41.25±134 vs. 49.46±11.49%) were characteristic for asthma. In nonatopic asthma patients inactivation of CD80 or CD86 blockade significantly reduced IFN-g production by T lymphocytes (p<0.02; p<0.03). In both studied groups anti-CD80 antibodies did not diminish T lymphocytes` production of IL-4. However anti-CD86 antibodies significantly (p<0.04) reduced the IL-4 concentration in culture supernatants. Our results confirm that both CD80 and CD86 molecules play on important role in the maintenance and amplification of inflammatory process. It suggests that in the inflammatory process that occurs in the nonatopic bronchial asthma Th1 as well as Th2 lymphocytes are equally important
Keywords: CD80 (B7.1), CD86 (B7.2), IL-4, IFN-g, monocytes, lymphocytes, nonatopic bronchial asthma.