XXXX -derived heat shock protein HSP70 functions as a B cell mitogen.

@entity19 @entity6414 @entity5001 @entity465 @entity1961 @entity1990 @entity3204
We have investigated the role of @entity3204 -derived heat shock protein 70 (TgHSP70) as a B cell mitogen by measuring proliferative responses in vitro. TgHSP70 induced prominent proliferative responses in @entity19 B cells derived not only from @entity3204 -infected but also from uninfected @entity19 . @entity19 responded to TgHSP70; however, severe @entity465 , RAG1-/- B6, and microMT @entity19 failed to respond. B220+ spleen cells showed marked proliferation after stimulation with TgHSP70, but neither @entity1961 + nor CD8+ population responded. This unresponsiveness of @entity1961 + and CD8- T cells to TgHSP70 was antigen presenting cells independent. These data indicate that TgHSP70 induced the proliferation of B cells but not T cells. @entity6414 , a potent inhibitor of lipopolysaccharide (LPS), did not eliminate TgHSP70-induced proliferation. C3H/HeN @entity19 responded well to TgHSP70 stimulation; however, C3H/HeJ @entity19 carrying a point mutation in the Toll-like receptor (TLR) 4 failed to respond. This indicates that @entity1990 is required for TgHSP70-induced B cell activation. The involvement of @entity1990 in the TgHSP70-induced proliferative responses of spleen cells was also shown by the use of @entity1990 -/- @entity19 . But TgHSP70-induced, but not LPS-induced, spleen cell proliferation was observed in @entity5001 -/- @entity19 , indicating that the @entity5001 molecule was involved in LPS-induced proliferation but not in TgHSP70-induced proliferation.
