Deliberate removal of T cell help improves virus-neutralizing antibody production

Abstract
The B cell response to lymphocytic choriomeningitis virus is characterized by a CD4+ T cell–dependent polyclonal hypergammaglobulinemia and delayed formation of virus-specific neutralizing antibodies. Here we provide evidence that, paradoxically, because of polyclonal B cell activation, virus-specific T cell help impairs the induction of neutralizing antibody responses. Experimental reduction in CD4+ T cell help in vivo resulted in potent neutralizing antibody responses without impairment of CD8+ T cell activity. These unexpected consequences of polyclonal B cell activation may affect vaccine strategies and the treatment of clinically relevant chronic bacterial, parasitic and viral infections in which hypergammaglobulinemia is regularly found.