Clinical and experimental immunology
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Clin. Exp. Immunol. · Jan 2000
Expression of costimulatory molecules CD80 and CD86 and their receptors CD28, CTLA-4 on malignant ascites CD3+ tumour-infiltrating lymphocytes (TIL) from patients with ovarian and other types of peritoneal carcinomatosis.
Costimulation of T lymphocytes by the leucocyte surface molecules CD80 and CD86 expressed on antigen-presenting cells (APC) is required for the development of T cell responses. The CD28 and CTLA-4 molecules on T cells serve as receptors for the CD80 and CD86 costimulatory antigens. We have examined the frequency of expression of CD80 (B7.1), CD86 (B7.2), CD28 and CTLA-4 surface antigens on TIL isolated from malignant ascites or peritoneal washings of 26 patients with ovarian carcinoma and five patients with non-ovarian peritoneal carcinomatosis. ⋯ An anti-CD86 MoAb or a combination of anti-CD86 and anti-CD80 MoAbs significantly inhibited the proliferation of cultured intraperitoneal TIL. We have shown that in addition to CD28 and CTLA-4, CD3+ intraperitoneal TIL express the costimulatory molecules CD80 and CD86. The expression of these molecules on T cells could be dependent upon certain factors in the tumour microenvironment that could determine the outcome of in vivo immune responses.
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Clin. Exp. Immunol. · Dec 1999
Gammadelta T cells in Behçet's disease (BD) and recurrent aphthous stomatitis (RAS).
The immunopathogenesis of BD is believed to be T cell-mediated. The objective of this study was to characterize the activation stage and cytokine profile of peripheral blood lymphocytes (PBL), with particular emphasis on gammadelta T cells. Venous blood was collected from 20 patients with BD, and for comparison, from 11 patients with RAS and from 15 healthy controls. ⋯ Furthermore, in BD a significantly increased proportion of the gammadelta T cell population expressed CD69 and high levels of CD29 and were induced to produce IFN-gamma and TNF-alpha compared with healthy controls. In contrast, an increased percentage of gammadelta T cells from RAS patients was induced to produce IFN-gamma, but not TNF-alpha. These results indicate that in BD, activated gammadelta T cells, capable of producing IFN-gamma and TNF-alpha, are present in peripheral blood, suggesting that gammadelta T cells are dynamic and may be regulating immunopathogenic events.
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Clin. Exp. Immunol. · Nov 1999
Perioperative serum levels of tumour-necrosis-factor alpha (TNF-alpha), IL-1 beta, IL-6, IL-10 and soluble IL-2 receptor in patients undergoing cardiac surgery with cardiopulmonary bypass without and with correction for haemodilution.
Cardiac surgery with cardiopulmonary bypass (CPB) leads to a systemic inflammatory response with secretion of cytokines. Alterations in the serum concentrations of cytokines have important prognostic significance. Reports on cytokine release during cardiac surgery with CPB have yielded conflicting results. ⋯ Cytokine measurements not corrected for haemodilution were significantly lower than the corrected values. The perioperative haemodilution and decrease in PCV may lead to an underestimation of the cytokine secretion in post-operative patients. We conclude that cytokine measurements were significantly influenced by the perioperative haemodilution and the subsequent decrease in PCV and may in part account for the varying results reported in the literature regarding cytokine release in patients undergoing CABG surgery.
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Clin. Exp. Immunol. · Sep 1999
Spleen autotransplantation provides restoration of functional splenic lymphoid compartments and improves the humoral immune response to pneumococcal polysaccharide vaccine.
After splenectomy, patients have an increased risk of overwhelming post-splenectomy infection (OPSI) or sepsis involving encapsulated bacteria such as pneumococcus. The value of spleen autotransplantation after splenectomy because of trauma has long been questioned. Much attention has been given to the restoration of mononuclear phagocyte system (MPS) function, which appeared to be similar to that of splenectomized individuals. ⋯ The titres were highest 3 days after vaccination. Immunohistochemical studies demonstrated structurally functional autotransplants, including an intact marginal zone. Considering this significant anti- pneumococcal antibody response, spleen autotransplants can be expected to enable an improved humoral response to PPS, and to contribute to protection against OPSI after splenectomy.
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Clin. Exp. Immunol. · Nov 1998
Interferon-gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha) are necessary in the early stages of induction of CD4 and CD8 cytotoxic T cells by Mycobacterium leprae heat shock protein (hsp) 65 kD.
Cytotoxic T cells (CTL) may play an important role in host defence against mycobacterial infections. CD4 CTL are preferentially induced by mycobacteria, but both CD4 and CD8 CTL may be necessary components of a protective immune response. The 65-kD mycobacterium heat shock protein (hsp65) is a poor inducer of CTL in multibacillary leprosy (MB) patients. ⋯ Down-regulation of CTL was observed by addition of IL-4, IL-10, anti-IFN-gamma or anti-TNF-alpha in N controls. Our data demonstrate that IFN-gamma and TNF-alpha must be present for at least the first 60 h of the induction stage in order to generate full hsp65 CTL. Hence, IFN-gamma and TNF-alpha would be key factors in the generation of hsp65 CTL.