Fas ligand (FasL) is a peptide that plays an important immunoregulatory role in limiting the host immune response. Several studies have shown that the expression of FasL in the anterior chamber of the eye and the testis allows these tissues to be immunoprivileged sites. Immunotolerance is achieved by binding of FasL to its receptor (Fas) on activated immune cells, which results in cell apoptosi...

Triggering of the TCR/CD3 complex with specific antigen or anti-CD3 monoclonal antibody initiates activation-induced cell death (AICD) in mature T cells, an effect also mediated by the Fas/FasL system. We have previously shown that CD2 stimulation rescues T cells from TCR/CD3-induced apoptosis by decreasing the expression of Fas and FasL. In the present study, we examined whether the endogenous...

Naive and memory B cells were isolated from human tonsils and examined for expression of APO-1/Fas and for their sensitivity to the APO-1-dependent apoptosis. APO-1 was found to be constitutively expressed on memory but not on naive B cells. The susceptibility of both cell types to the APO-1 apoptotic pathway was acquired upon CD40 triggering and was correlated with increased expression of the ...

The pathomechanism of Helicobacter pylori action upon gastric mucosa and its role in the pathogenesis of gastritis have not been fully elucidated. The aim of this study was to evaluate the most prevalent lymphocyte subpopulations of the gastric mucosa in gastritis in children, as well as to evaluate the expression of Fas and Fas ligand receptors (FasL), periapoptotic markers of gastric mucosa l...

Recent studies from our laboratory demonstrated that mucosal lymphoid tissue such as Peyer's patch cells and lamina propria (LP) B lymphocytes from mice shows evidence of increased apoptosis after sepsis that is associated with localized inflammation/activation. The mechanism for this is poorly understood. Endotoxin as well as Fas/Fas ligand (FasL) have been shown to augment lymphocyte apoptosi...