Abstract
Staphylococcal enterotoxins are potent superantigens, in that they activate T cells bearing specific Vβ-chain gene segments. In this study, we analyzed the capacity of staphylococcal enterotoxin D (SED) to function as a B cell superantigen. SED induced T cell-dependent polyclonal proliferation and differentiation of B cells. In the absence of T cells, SED induced survival of B cells uniquely expressing VH4 containing IgM. The mechanism of survival of VH4-expressing B cells appeared to relate to the countering of apoptosis initiated by the engagement of HLA-DR by SED. Analysis of the VH4 gene products expressed by SED-stimulated B cells revealed the usage of six of the known functional VH4 genes with a variety of different CDR3 regions, employing different DH and JH gene segments. Moreover, the sequence analysis identified a possible site for SED binding of VH4 that includes the solvent-exposed surfaces of 3′ CDR2/FR3 and/or FR1. Thus, SED appears to function as a unique B cell superantigen by inducing survival of VH4-expressing B cells.
Original language | English (US) |
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Pages (from-to) | 3608-3620 |
Number of pages | 13 |
Journal | Journal of Immunology |
Volume | 156 |
Issue number | 10 |
State | Published - May 15 1996 |
ASJC Scopus subject areas
- Immunology and Allergy
- Immunology