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: Reduced susceptibility to Fas-mediated apoptosis in B-1 cells. Author: Masuda K, Wang J, Watanabe T. Journal: Eur J Immunol; 1997 Feb; 27(2):449-55. PubMed ID: 9045916. Abstract: Elimination of activated T and B cells by Fas-dependent apoptosis may contribute to the maintenance of peripheral tolerance. CD40 ligation was recently shown to up-regulate Fas expression and enhance susceptibility to Fas-mediated apoptosis in mouse splenic B cells. In the present study, we have investigated the regulation of Fas expression and Fas-triggered apoptotis in mouse peritoneal B-1 cells. B-1 cells expressed a similar level of CD40 as that on B-2 cells, and proliferated in response to a soluble CD40 ligand (CD40L)-CD8alpha chimeric protein, suggesting that CD40 on B-1 cells is functional. In contrast to B-2 cells, B-1 cells expressed Fas at only low levels in response to CD40L-CD8alpha alone or CD40L-CD8alpha + interleukin-4, and were resistant to Fas-mediated apoptosis following these treatments. While Fas expression could be induced in B-1 cells to a comparable level as that in B-2 cells by cross-linking CD40L-CD8alpha with an anti-CD8alpha antibody, the sensitivity to Fas-mediated apoptosis in B-1 cells was significantly reduced compared with B2 cells. These results suggest that peritoneal B-1 cells from normal mice have a lower susceptibility to Fas-mediated apoptosis and may distinguish B-1 from B-2 cells. Similarly, B-1 cells from the peritoneal cavity and spleen of autoimmune-prone NZB mice exhibited reduced susceptibility to Fas-mediated apoptosis relative to their B-2 counterparts. NZB splenic B-1 cells, however, were more susceptible to Fas-mediated apoptosis than NZB peritoneal B-1 cells. The results presented here raise the possibility that the reduced susceptibility to Fas-triggered apoptosis in B-1 cells might be an accelerating factor for the autoantibody production in NZB mice.[Abstract] [Full Text] [Related] [New Search]