CONTENTS
Review
- The Immunopathology of Primary Biliary Cirrhosis: Thoughts for the Millennium
MOTOKO SASAKI, AFTAB A. ANSARI, YASUNI NAKANUMA, ROSS L. COPPEL, EMMET B. KEEFFE5 and M. ERIC GERSHWIN1Abstract. Primary biliary cirrhosis is an organ specific autoimmune disease that produces progressive cholestatic liver failure. It is predominantly a disease of women characterized by chronic progressive destruction of small intrahepatic bile ducts with portal inflammation and ultimately fibrosis. The serologic hallmark of primary biliary cirrhosis (PBC) is the presence of antibodies to mitochondria. The mechanisms by which and if which such antibodies produce liver tissue injury is unknown. However, the presence of these antibodies have allowed detailed immunological definition of the antigenic epitopes, the nature of reacting autoantibodies and the characterization of T cell responses. Several mechanisms may now be proposed regarding the immune mediated bile duct damage in PBC, including the possible role of T cell-mediated cytotoxicity and intracellular interaction between the IgA class of antimitochondrial antibodies (AMA) and mitochondrial autoantigens. The advent of molecular biology, the ability to clone and define epitopes, and the use of in situ nucleic acid hybridization, have all led to advances in understanding the natural history of immunopathology in PBC. There are major questions which remain unanswered, including, of course, etiology, but also including the questions of why there is female predominance, the absence of PBC in children, the relative ineffectiveness of immunosuppressive drugs, and the specific role of mitochondrial antigens. In this review, we focus on these issues and particularly on the immunobiology of patients with this disease.
Keywords: primary biliary cirrhosis; autoimmunity; mitochondria; pyruvate dehydrogenase.
- Molecular Aspects in the Pathogenesis of Human Systemic Lupus Erythematosus
STAMATIS-NICK C. LIOSSIS, and GEORGE C. TSOKOSAbstract. Systemic lupus erythematosus is a common and often devastating systemic autoimmune disease of unknown etiology. In this communication we review the latest developments of the molecular pathogenesis of human lupus. Novel genetic studies of multiplex lupus families have revealed potential disease-associated genome intervals, put special emphasis on genetic loci mapping in the long arm of chromosome 1 and have underscored the complexity of the underlying genetic background. New data have emerged on the role of estrogens in the function of lymphocytes and a number of studies have recently emphasized the relative Th-1/Th-2 cytokine imbalance in favor of a Th-2 type cytokine immune response. Finally, novel experiments have revealed an abnormal antigen receptor- -mediated signaling process in lupus T and B cells, which may influence the aberrant expression and function of costimulatory molecules as well as of other aspects of immune cell function. It is important to decipher the underlying molecular mechanisms that govern the expression of human lupus, because we may design novel, rational approaches in the treatment of a human lupus, a disease that has high morbidity and mortality.
Keywords: autoimmunity; lymphocytes; antigen receptor; signal transduction; costimulatory molecules.
- Preventing Staphylococcal Disease by Disarming the Immune Responses to Infection
ANDREJ TARKOWSKIAbstract. Use of experimental models of staphylococcal infections clarified several bacterial virulence factors as well as many hematopoetic cell types and their products that are involved in the pathogenesis of infection. For many decades it has been believed that antibody mediated response to staphylococci and their products was the major, if not the only one, hallmark of immune reactivity during infection. Recent studies have documented that T cell mediated responses to superantigens produced by staphylococci are not only prominent but also decisive with respect to sequels. Also the nonantigen specific immune responsiveness to staphylococcal infection is reviewed including roles of neutrophils, complement system and nitric oxide. The knowledge gained regarding staphylococcal virulence factors and the host immune responses has prompted researchers to develop new strategies how to interact in vivo witl the infectious process. Some of these approaches are commented in this review regarding e. g. vaccination procedures in order to prevent severe infections as well as therapeutic procedures to minimize organ damage during an ongoing infectious process.
Keywords: Staphylococcus aureus; vaccination; virulence immunity; T cells; B cells; cytokines; CpG oligonucleotides.
- Crosstalk Between G Protein-Coupled Receptors and Tyrosine Kinase Signaling: Src Take Centre Stage
ANDRZEJ PTASZNIK and ALAN M. GEWIRTZAbstract. Although the role of G protein-coupled receptors in the regulation of metabolic, secretory and contractile responses is well established, they have only recently been recognized as important mediators of cellular growth and differentiation. G protein-coupled signaling pathways had been previously thought to be totally independent of the tyrosine kinase receptor pathway. It was previously believed that molecular switches responsible for growth factor tyrosine kinase receptor signaling and G protein-coupled signaling were divided into a distinct sets of protein families. Recent evidence has demonstrated, however, that G protein-coupled receptors can crosstalk to tyrosine kinase signaling. In the past few years several groups have found that G protein-coupled receptors utilize non-receptor tyrosine kinases, mostly that of Src family, and some adapter proteins, to regulate tyrosine kinase cascades in cells.
Keywords: signal transduction; Src kinase; Shc protein; PI 3-kinase.
Clinical and Cellular Immunology
- Effective Phage Therapy is Associated with Normalization of Cytokine Production by Blood Cell Cultures
BEATA WEBER-DĄBROWSKA1, MICHAŁ ZIMECKI2 and MARIAN MULCZYK1Abstract. The aim of this study was to investigate the effect of phagotherapy on tumor necrosis factor a (TNF-a) and interleukin 6 (IL-6) serum levels and the ability of blood cells to produce these cytokines in culture. Fifty one patients with long-term, suppurative infections of various tissues and organs were enrolled. The ability of cells to secrete cytokines was tested using whole blood cell cultures, unstimulated or stimulated with lipopolysaccharide (LPS) from E. coli. In addition, cytokine serum levels were determined. Measurement of cytokine activity was performed using bioassays. We showed that TNF-a, but not IL-6 serum levels, were regulated upon division of patients into categories exhibiting initial: low, moderate and high cytokine levels. The low spontaneous production of IL-6 by blood cell cultures was elevated significantly on day 21 of phage therapy, whereas high release of this cytokine was inhibited. No such correlation was observed with LPS-induced IL-6 production in cell cultures when cells from low-, moderately- or highly-reactive patients were studied. Phage therapy modified TNF release according to the initial ability to produce that cytokine: it reduced TNF production in high responders and increased it in low responders. Patients infected only with Gram-positive bacteria demonstrated analogous changes in the spontaneous and LPS-induced TNF-a production as in the whole studied group. A similar kind of regulation was observed in TNF-a and LPS-induced production, i. e. low production was significantly elevated, high strongly inhibited, and moderate only slightly affected. In summary, we demonstrated for the first time that effective phage therapy can normalize TNF-a serum levels and the production of TNF-a and IL-6 by blood cell cultures.
Keywords: phage therapy; TNF-a; IL-6; blood cell cultures.
- Abnormal Distribution of gd T Lymphocytes in Graves’ Disease and Insulin-Dependent Diabetes Type 1
ADAM KRĘTOWSKI, JANUSZ MYŚLIWIEC and IDA KINALSKAAbstract. There is an increasing evidence that CD3+ cells, bearing gd T cell receptors representing a minor subpopulation of T cells in the peripheral blood of humans are involved in the development of autoimmunity. The aim of the present study was determination of the gd T cell subpopulation levels in the peripheral blood of subjects with Graves’ disease and newly diagnosed type 1 diabetes in comparison to age-matched healthy controls. The percentages of CD3+, CD8+, gd TCR+CD8+, gd TCR+CD8– lymphocyte subsets were measured by flow cytometry. In the peripheral blood of newly diagnosed Graves’ disease patients we showed a significant decrease of gd TCR+ cells and gd TCR+CD8– subset content in comparison to the percentages observed in subjects after methimazole treatment and in healthy controls. We also found a significant increase of gd TCR+CD8+ cells in the peripheral blood of subjects with insulin-dependent diabetes, treated with insulin for 3–6 months. The present findings confirm our previous hypothesis that gd TCR+CD8+ lymphocyte subset could play a role in the pathogenesis of diabetes type 1, probably as regulatory T cells and could be induced by delivery of exogenous insulin. Our results suggest that gd T cells (gd TCR+CD8– subset) could also play an important role in the development of Graves’ disease and that their levels are modulated by thyreostatic treatment.
Keywords: gd TCR+ lymphocytes; Graves’ disease; type 1 diabetes mellitus.
- Changes in Glucocorticoid-Induced Apoptosis and in Expression of Bcl-2 Protein During Long-Term Culture of Thymic Lymphoma
MARCIN KOBZDEJ, JANUSZ MATUSZYK, EWA ZIOŁO and LEON STRZĄDAŁAMARCIN KOBZDEJ, JANUSZ MATUSZYK, EWA ZIOŁO and LEON STRZĄDAŁAAbstract. Lymphomagenesis is a multistep process progressively freeing transformed thymocytes from external regulatory signals, i. e. thymic developmental program controlling growth, differentiation or apoptosis. Here we report that cells of thymic lymphoma overexpressing Ras/Raf proteins, initially resistant to TCR-dependent apoptosis but sensitive to dexamethasone- and etoposide-induced cell death, became insensitive to dexamethasone after long-time culture. That transition correlated with a strong increase in the expression of the anti-apoptotic Bcl-2 protein. Interestingly, lymphoma cells were still sensitive to p53-mediated apoptosis induced by etoposide. It suggests that the anti-apoptotic activity of Bcl-2 is correlated with a resistance to glucocorticoid-induced apoptosis but not to p53-mediated apoptosis. The sequence of mutations in the process of lymphomagenesis seems to be composed of at least 3 main hits which equip the cells with independence from external mitogenic signals (activation of Ras/Raf), resistance to inducers of apoptosis (activation of Bcl-2) and generation of cellular heterogeneity (deletion of p53) important in tumor progression.
Keywords: thymic lymphoma; Bcl-2; dexamethasone; apoptosis; long-term culture.
Various
- HLA-DR Antigens in Patients with Pulmonary Tuberculosis in Northern Poland. Preliminary Report
ANNA DUBANIEWICZAbstract. The aim of the present study was the analysis of the association between particular class II HLA antigens and the incidence of tuberculosis in northern Poland. HLA-DR antigens in a group of 26 patients with pulmonary tuberculosis (PTB) and 58 healthy volunteers were determined. Histocompatibility typing was performed by the PCR-SSP method using primers from the Dynal company. For statistical analysis, the c2 test was used with Yates’ correction. The probability values were weighted for the number of antigens tested (pc). The relative risk (RR) was calculated by Woolf’s method. We found that HLA-DR16(2) antigen expression was significantly higher in patients with tuberculosis than in the tested group of healthy controls (p<0.001, pc< 0.01); the highest relative risk (RR = 12. 4) of tuberculosis incidence was connected with DR16(2) antigen, the prevalence of HLA-DR13(6) antigen was significantly lower in pulmonary tuberculosis (with RR = 0. 09) than the control (p< 0. 001, pc< 0. 01). The results obtained suggest that the presence of HLA-DR16(2) antigen can extend the risk of developing tuberculosis whereas HLA-DR13(6) antigen occurrence was significantly more rare in pulmonary tuberculosis than in healthy individuals and that the relative risk (RR = 0. 09) can be connected to their relation with the genes of insusceptibility to tuberculosis.
Keywords: HLA-DR; pulmonary tuberculosis.
- Novel Ru(III), Rh(III), Pd(II) and Pt(II) Complexes with Ligands Incorporating Azole and Pyrimidine Rings. I. Antiproliferative Activity in Vitro
MAREK Z. WIŚNIEWSKI1, JOANNA WIETRZYK2 and ADAM OPOLSKI2
Abstract. A number of co-ordination compounds of Ru(III), Rh(III), Pd(II) and Pt(II) with ligands incorporating azole and pyrimidine rings has been synthesized. The in vitro cell proliferation-inhibitory activity of these compounds was examined against human cancer cell lines: A 549 (lung carcinoma), LS-180 (colon cancer) and MCF-7 (breast cancer), using SRB technique. Six out of 13 compounds studied revealed cytotoxic activity in vitro. Inhibitory dose 50% (ID50) was lower than 4 mg/ml, which is an activity criterion accepted in conventional in vitro cytotoxic screening tests. Two compounds revealed weak cytotoxic activity with ID50 higher than 4 mg/ml and five compounds were inactive.
Keywords: azole and pyrimidine complexes; platinum-group metal complexes; cytotoxic activity in vitro; human cancer cell lines.