BCG, CORYNEBACTERIUM-PARVUM OR MYCOBACTERIUM-LEPRAE ADDED TO CULTURES OF BCG-PRIMED MOUSE SPLEEN-CELLS CAUSE AN ENHANCED PRIMARY ANTIBODY-RESPONSE INVITRO

Abstract

A few wk after mice were injected i.v. with 108 live Mycobacterium bovis, BCG, the antibody response of their spleen cells to SRBC [sheep red blood cells] in vitro was comparable with the response of cells from untreated mice. BCG organism addition to the culture vessels resulted in enhanced antibody-forming cell (AFC) responses by the primed cells but not by the cells from the untreated mice. No evidence was found for a direct stimulation of B cells and cell depletion experiments suggested macrophages were directly involved. BCG added to the cultures up to 68 h after they were set up, but not later, still caused enhancement. No enhancement was found when dinitrophenyl-Ficoll was used as antigen. The ability to stimulate the anti-SRBC response was not restricted to the organism used for priming. Enhacement was also found ifC. parvaum or M. leprae were added to BCG-primed cells and if BCG was added to C. parvum-primed cells. The relevance of the results to the search for a leprosy vaccine is discussed.