Related Experiment Video
Updated: Oct 2, 2026

Isolation of Group 2 Innate Lymphoid Cells from Mouse Nasal Mucosa to Detect the Expression of CD226
Published on: May 10, 2022
Fas ligand-expressing B-1a lymphocytes mediate CD4(+)-T-cell apoptosis during schistosomal infection: induction by
1Department of Immunology and Microbiology, Wayne State University, School of Medicine, Detroit, Michigan 48201.
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.
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.
Related Concept Videos
T Cell Types and Functions
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
The Extrinsic Apoptotic Pathway
T Cell Activation and Clonal Selection
Naive T cells that have not yet encountered an antigen express two primary CD...
The Intrinsic Apoptotic Pathway
B Cell Activation and Differentiation
When naive B cells encounter a specific antigen that can bind to the B cell receptor (BCR) on their surface, they undergo sensitization to respond to the antigen's presence. Sensitization begins with...
Cytotoxic T Cells-mediated Immune Response
Immunological surveillance is the ability of immune cells to monitor and eliminate infected cells with intracellular pathogens, neoplastically transformed cells, and cells with non-self antigens. Cytotoxic T cells and NK...

