Activated B cells can deliver help for the in vitro generation of antiviral cytotoxic T cells.
The experiments described in this paper show that activated B cells can deliver help for antiviral cytotoxic T (Tc) cell responses in vitro. This conclusion is based on four observations. (i) Influenza viruses induced secondary Tc cell responses in vitro in the absence of CD4+ T cells. This capacity correlated with the B-cell mitogenicity of these viruses. (ii) Depletion of both CD4+ T cells and B cells prevented the generation of anti-influenza Tc cell responses, whereas depletion of either CD4+ T cells or B cells alone failed to do so. In addition, supplementation of unprimed B cells restored the Tc cell responsiveness of primed splenocytes that had been depleted of both CD4+ T cells and B cells. (iii) Contact between T and B cells was not obligatory for the delivery of B-cell helper signal, and hence help was mediated by a soluble factor(s). (iv) Lipopolysaccharide-activated B cells could replace the CD4+ T-cell requirement in the induction of Tc cell responses to nonmitogenic influenza virus in vitro.
Liu
Y
Y
Division of Cell Biology, John Curtin School of Medical Research, Australian National University, Canberra City ACT 2601.
Müllbacher
A
A
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D007111:Immunity, Cellular; D009980:Influenza A virus / Q000276:immunology*; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008815:Mice, Inbred Strains; D012397:Rosette Formation; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000145:classification; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014616:Vaccinia virus / Q000235:genetics*