These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Soluble egg antigen-stimulated T helper lymphocyte apoptosis and evidence for cell death mediated by FasL(+) T and B cells during murine Schistosoma mansoni infection.
    Author: Lundy SK, Lerman SP, Boros DL.
    Journal: Infect Immun; 2001 Jan; 69(1):271-80. PubMed ID: 11119515.
    Abstract:
    Granuloma formation around schistosomal eggs is induced by soluble egg antigens (SEA) and mediated by the activity of CD4(+) Th lymphocytes and their cytokines. Regulation of the inflammatory Th cell response during infection is still insufficiently understood. The hypothesis of this study was that activation-induced cell death (AICD) of CD4(+) T cells is involved in the immune inflammatory response. This study investigated the dynamics of splenic and granuloma CD4(+) Th cell apoptosis and Fas ligand (FasL) expression during the acute and chronic stages of murine schistosomal infection. Enhanced apoptosis of freshly isolated CD4(+) Th lymphocytes commenced after egg deposition and persisted during the peak and modulated phases of granuloma formation. After oviposition, CD4(+), CD8(+), and CD19(+) splenocytes and granuloma cells expressed elevated levels of FasL but FasL expression declined during the downmodulated stage of infection. In culture, SEA induced splenic and granuloma CD4(+) T-cell apoptosis and stimulated expression of FasL on splenic but not granuloma CD4(+) T cells, CD8(+) T cells, and CD19(+) B cells. SEA-stimulated splenocytes and granuloma cells preferentially lysed a Fas-transfected target cell line. Depletion of B cells from SEA-stimulated splenic cultures decreased CD4(+) T cell apoptosis. Coculture of purified splenic B cells with CD4(+) T cells and adoptive transfer of purified B cells indicated that antigen-stimulated B cells can kill CD4(+) Th cells. However, CD4(+) T cells were the dominant mediators of apoptosis in the granuloma. This study indicates that AICD is involved in the apoptosis of CD4(+) T cells during schistosomal infection.
    [Abstract] [Full Text] [Related] [New Search]