Study of asialogangliosides on surface membranes of rat bone marrow cells and macrophages.

The presence of asialogangliosides on membrane surfaces of rat bone marrow cells and macrophages was studied by an immunological method using anti-glycolipid antibodies with high specificity. The antibodies against N-acetylgalactosaminyl(beta 1-4)galactosyl(beta 1-4)glucosylceramide (GA2), galactosyl(beta 1-3)N-acetylgalactosaminyl(beta 1-4)galactosyl(beta 1-4)glucosylceramide (GA1) and fucosyl(alpha 1-2)galactosyl(beta 1-3)N-acetylgalactosaminyl(beta 1-4)galactosyl(beta 1-4)glucosylceramide (Fuco-GA1) were prepared, and used for cytotoxicity testing and indirect staining by the immunofluorescence technique. In the cytotoxicity test, approximately 40-50% of rat intraperitoneal macrophages were killed by each of the anti-glycolipid antisera. This finding was confirmed by the indirect immunofluorescence staining method with the purified anti-GA2, anti-GA1, and also anti-Fuco-GA1 IgG. When a rat was preimmunized with bovine serum albumin, all macrophages induced in ascites fluid were found to possess GA1 by the staining method. Immature granulocytes were stained specifically with the anti-GA2 antibody. Granulocytes, myelocytes, and megakaryocytes were stained with the anti-GA1 antibody. Blastic myelocytes were stained with the anti-Fuco-GA1 IgG, but lymphocytes were not stained with any of these anti-asialoganglioside antibodies. From these observations, free-type cells such as macrophages and bone marrow cells were found to possess asialogangliosides as membrane components.