Fas Ligand-Expressing B-1a Lymphocytes Mediate CD4+-T-Cell Apoptosis during Schistosomal Infection: Induction by Interleukin 4 (IL-4) and IL-10
AUTOR(ES)
Lundy, Steven K.
FONTE
American Society for Microbiology
RESUMO
A previous study of the murine model of Schistosoma mansoni infection has implicated splenic CD19+ B lymphocytes as Fas ligand (FasL)-bearing mediators of CD4+ T-lymphocyte apoptosis. The present study shows that B-cell deficiency leads to decreased CD4+ T-cell apoptosis during infection and compares FasL expression and killer function of B-1a- and CD5− B-lymphocyte subsets. B-1a cells from uninfected mice displayed constitutive expression of FasL compared with that of CD5− B cells. FasL expression was enhanced following worm egg deposition and antigenic stimulation on both subsets of B cells. Purified B-1a cells from uninfected mice were potent effectors of CD4+ T-cell apoptosis, and the killing effect was enhanced during schistosome infection. FasL expression by splenic B cells required CD4+-T-cell help that was replaced by addition of culture supernatants from antigen-stimulated splenocytes of infected mice. The culture-supernatant-stimulated FasL expression was inhibited by anti-interleukin 10 (IL-10) and anti-IL-4 antibodies. Culture of purified B cells with recombinant IL-4 (rIL-4), rIL-10, and soluble egg antigens (SEA) led to increased expression of FasL on B-1a cells. These results suggest that FasL-expressing, splenic B-1a cells are important mediators of SEA-stimulated CD4+-T-cell apoptosis and that maximal FasL expression on B-1a cells is dependent on antigenic stimulation and the presence of IL-4 and IL-10.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=127725Documentos Relacionados
- Role of Interleukin-4 (IL-4) and IL-10 in Serum Immunoglobulin G Antibody Responses following Mucosal or Systemic Reovirus Infection
- Development of a System To Study CD4+-T-Cell Responses to Transgenic Ovalbumin-Expressing Toxoplasma gondii during Toxoplasmosis
- Oral immunization of interleukin-4 (IL-4) knockout mice with a recombinant Salmonella strain or cholera toxin reveals that CD4+ Th2 cells producing IL-6 and IL-10 are associated with mucosal immunoglobulin A responses.
- CD4+-T-cell counts, spontaneous apoptosis, and Fas expression in peripheral blood mononuclear cells obtained from human immunodeficiency virus type 1-infected subjects.
- Contribution of Interleukin-12 (IL-12) and the CD28/B7 and CD40/CD40 Ligand Pathways to the Development of a Pathological T-Cell Response in IL-10-Deficient Mice