INDUCTION OF SUPPRESSOR ADHERENT CELLS BY INJECTING HEAVY DOSE OF LIVE BCG

I. In Vitro Analysis of Suppression of BCG Cell Wall Induced Delayed Type Hypersensitivity

Abstract

Previous injection of live BCG in mice produced a suppression of delayed hypersensitivity induced by oil-treated BCG cell walls (CW). This phenomenon was analyzed by the macrophage migration inhibition (MI) test in which peritoneal exudate cells (PEC) from live BCG-injected mice were mixed with PEC from BCG CW-immunized mice, and observed the former's suppression on the MI activity of the latter. The author examined the cell population involved in this suppression and found that the adherent cells of PEC did possess a suppressive effect which was retained even after treatment with either anti-mouse Ig serum or anti-brain associated θ antigen serum. This suggests that the suppressor cell may belong to macrophage compartments.Furthermore, whether or not the suppression of delayed-type hypersensitivity by the pretreatment with live BCG is antigen-specific was examined in mice immunized with heat-killed Listeria monocyto genes. As a result, the live BCG-pretreatment produced a significant suppression of footpad response induced with Listeria antigen, suggesting that this suppression is not-antigen-specific.