[A change in antigen presentation ability of spleen macrophage from Balb/c mouse during late pregnancy].

OBJECTIVE:To study the antigen presentation ability of spleen macrophage from Balb/c mouse during late gestation. METHODS:The spleen of Balb/c mouse during late gestation was collected aseptically and macrophage was separated; the mice in estrus were used as control. The ability of macrophage to prime original T cells to human gamma globulin antigen (HGG-Ag) or placenta antigen (Pla-Ag) was evaluated by a delayed-type hyper sensitivity (DTH) response induced by the same antigen, and the ability of macrophage to induce the proliferation of primed normal T cells to HGG-Ag or Pla-Ag was assessed by an antigen special lymphocyte transformation in vitro. RESULTS:After being sensitized previously by spleen macrophage from Balb/c mice during late gestation that has been pulsed by HGG-Ag or Pla-Ag, the DTH intensity of mice response to the same antigen was significantly weaker than that being sensitized by macrophage from mice in estrus (P < 0.05). When spleen macrophage from Balb/c mice during late gestation was used as antigen presentation cell (APC), the proliferability of primed T cell induced by HGG-Ag or Pla-ag was significantly lower than that when macrophage from estrous Balb/c mouse was used in vitro (P < 0.05). CONCLUSION:The antigen presentation ability of spleen macrophage from Balb/c mouse is inhibited during late pregnancy. This may be the important mechanism by which maternal immune system tolerates embryo antigen and may be responsible for the down-regulation of maternal cell mediated immunity during pregnancy.