Functional characteristics of Peyer's patch lymphoid cells. I. Induction of humoral antibody and cell-mediated allograft reactions.

Peyer's patches from normal mice contain antigen-sensitive B and T cells, but lack the accessory adherent cell type(s) required both for the induction of humoral immune responses and for the induction of allograft reactions against cell surface alloantigens. Immune responsiveness can be restored to cultures of Peyer's patch cells by the addition of either APEC or ME. Peyer's patch B cells can be specifically induced by antigen to synthesize humoral antibody. Peyer's patch T cells can cooperate in B-cell induction and can be induced to mediate an allograft reaction against an allogeneic stimulus. Peyer's patch lymphoid aggregates appear to be a storehouse of antigen-sensitive cells sequestered in such a way as to lack an accessory cell type or factor required for induction,