Cellular and Humoral Immune Response of Germfree Mice Stimulated with 7S HGG or Salmonella Typhimurium

Abstract

Summary Germfree mice stimulated with either 7S HGG or Salmonella typhimurium vaccine react in a manner comparable to that of their conv counterparts. In each case the proliferation time of lymphoid cells was reduced from 21 to 22 hr in nonstimulated mice to 17 to 20 hr or 8 to 13 hr in mice stimulated with 7S HGG or S. typhimurium, respectively. Plasmacytopoiesis and hyperplasia was more pronounced in both groups when they were stimulated with the bacterial antigen. Plasmacytic cells, blast cells and large lymphocytes showed a proportionately greater increase in germfree mice than in conv mice following stimulation with either antigen, suggesting that, even if the germfree animal has fewer competent cells, these cells are less committed due to lack of previous antigenic stimulations. In vivo antibody production in the germfree-conv model shows a direct relationship to the amount of antibody-producing cells found in these animals, suggesting that this model may be a tool for studies on the kinetics of antibody formation in in vivo nonirradiated conditions.