Expression of B220 on activated T cell blasts precedes apoptosis

Eur J Immunol. 1998 Feb;28(2):540-7. doi: 10.1002/(SICI)1521-4141(199802)28:02<540::AID-IMMU540>3.0.CO;2-Y.

Abstract

Superantigens are bacterial or viral products that polyclonally activate T cells bearing certain TCR beta chain variable elements. For instance, Vbeta8+ T cells proliferate in response to staphylococcal enterotoxin B (SEB) in vivo and then undergo Fas- and/or TNF-mediated apoptosis. We have recently shown that apoptotic SEB-reactive T cells express the B cell marker B220. Here we report the identification of a novel subset of CD4+ B220+ T cell blasts that are the precursors of these apoptotic cells in SEB-immunized mice. Moreover, we show that the CD4- CD8- B220+ T cells that accumulate in the lymphoid organs of Fas ligand-defective gld mice stably express a form of the B220 molecule which exhibits biochemical similarities to that expressed by activated wild-type T cells, but is distinct from that displayed on the surface of B cells. Surprisingly, we also find a population of CD4+ B220+ pre-apoptotic T cells in FasL-defective gld mice, arguing that these cells can be generated in a Fas-independent fashion. Collectively, our data support a general model whereby upon activation, T cells up-regulate B220 before undergoing apoptosis. When the apoptotic mechanisms are defective, T cells presumably down-regulate their coreceptor molecules but retain expression of B220 as they accumulate in lymphoid organs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Annexin A5 / analysis
  • Apoptosis / immunology*
  • B-Lymphocytes / immunology
  • Blotting, Western
  • CD4 Antigens / analysis
  • Enterotoxins / pharmacology
  • Leukocyte Common Antigens / analysis
  • Leukocyte Common Antigens / biosynthesis*
  • Lymphocyte Activation*
  • Lymphoproliferative Disorders / genetics
  • Lymphoproliferative Disorders / immunology
  • Lymphoproliferative Disorders / pathology
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Staphylococcus aureus / immunology
  • T-Lymphocyte Subsets / enzymology*
  • T-Lymphocyte Subsets / immunology*
  • Up-Regulation / immunology

Substances

  • Annexin A5
  • CD4 Antigens
  • Enterotoxins
  • enterotoxin B, staphylococcal
  • Leukocyte Common Antigens