Detection of mannose-binding proteins on mouse lymphocytes

D-Mannose influences both the allogeneic stimulation of mouse spleen cells and the induction of cytotoxic T-lymphocytes. At low concentrations (10(-3) -4 x 10(-3) M), D-mannose increases [3H]thymidine incorporation and induction of cytotoxic cells. Higher concentrations lead to an inhibition of the allogeneic response. To test the involvement of mannose receptors, unstimulated and allogeneically stimulated spleen cells were lysed and the proteins electrophoretically separated. After blotting, the D-mannose-binding structures were identified by means of a biotinylated mannose-neoglycoprotein and avidin peroxidase. Two mannose-binding proteins of unstimulated mouse spleen lymphocytes with a molecular mass of 29 and 31 kDa were detected. In vitro allogeneically stimulated spleen lymphocytes show three other mannose-binding proteins with a molecular mass of 53, 65, and 76 kDa.