Borrelia burgdorferi enhances the costimulatory activity and cytokine production of APC.

Journal/Book: Z Rheumatol 1999; 58 Suppl. 1: I/51 (P 49). 1999;

Abstract: 1Deutsches Rheuma Forschungszentrum 2Medizinische Universitätsklinik III Charité Berlin Differential upregulation of costimulatory molecules by microorganisms such as Borrelia burgdorferi (Bb) could help to bias the host's immune response to the pathogen and help microbial persistence or the induction of immunopathology including autoimmunity. We have previously reported that Bb and lipopeptides (Lp) derived from its outer surface lipoproteins influence the immune response by upregulating CD80 and CD86 on B cells and CD80 on macrophages. Currently we are investigating the effect of Bb on the expression of CD40 on different APC populations. Furthermore we are also examining how Bb influences the expression of CD28 and CD40L the ligands for CD80/CD86 and CD40 respectively on T cells. Our recent data indicate that Bb upregulates the expression of CD40 on B cells macrophages and dendritic cells but does not seem to affect Ihe expression of costimulatory ligands on T cells. Regarding the cytokine production we are analyzing the influence of Bb on IL-12 IL-10 IL-6 and TNF-alpha production. Our preliminary results show that both pro-inflammatory and anti-inflammatory cytokines become upregulated in the presence of Bb indicating a general and probably unspecific activation of antigen presenting cells. Thus Bb induces in APC the production of cytokines that could support either Th1 or Th2 phenotype development in T cells. However we have reported earlier Bb induces Th1 but not Th2 differentiation. This suggests that Bb-mediated modulation of the immune response results from the addition of different effects and the activation and participation of different cell populations. Furthermore our data show that Bb induces a "proinflammatory milieu capable of sustaining the chronic inflammation that is typical of late manifestations of Lyme disease. le

Zurück | Weiter