A bacterial-induced lectin which triggers hemocyte coagulation in Manduca sexta

An inducible hemagglutinin termed M13, was purified from M. sexta hemolymph. M13 is a glucose-specific lectin which in addition to erythrocyte agglutination, can activate dedifferentiation of various hemocytes into a filamentous coagulation network. When lectin activity was inhibited with glucose or antiserum, neither erythrocyte agglutination or hemocyte coagulation occurred. When M13 was boiled or trypsin treated, hemocyte activation was lost, but erythrocyte agglutination remained. Hence M13 activity appears to be bimodal, possessing both a lectin activity and a hemocyte-coagulating activity.