Flow cytometric analysis reveals the presence of asialo GM1 on the surface membrane of alloimmune cytotoxic T lymphocytes.
Previous studies have demonstrated that natural killer (NK) cells express the glycolipid asialo GM1, as evidenced by the sensitivity of NK cells to treatment with anti-asialo GM1 serum and complement. Because alloimmune cytotoxic T lymphocytes (CTL) were found to be insensitive to treatment with anti-asialo GM1 serum and complement, it was concluded that asialo GM1 is expressed by NK but not by CTL. However, fluorescence studies indicated that a significant proportion of peripheral T cells did express asialo GM1. Flow cytometric studies were undertaken to determine the extent to which alloimmune CTL express asialo GM1. Affinity-purified, monospecific IgG anti-asialo GM1 antibodies were used to label cells from mixed lymphocyte cultures. Separation of asialo GM1-positive and -negative fractions by cell sorting revealed that the majority of CTL activity resides in the asialo GM1-positive population. When these studies are compared with similar studies of splenic NK activity, it is apparent that, despite the relative insensitivity of CTL to treatment with anti-asialo GM1 and complement, both CTL and NK activity are enriched in the asialo GM1-positive cell population obtained by cell sorting.
D000818:Animals; D000954:Antigens, Surface / Q000032:analysis* / Q000276:immunology; D003165:Complement System Proteins / Q000502:physiology; D003602:Cytotoxicity, Immunologic; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D005677:G(M1) Ganglioside; D006028:Glycosphingolipids / Q000032:analysis* / Q000276:immunology; D007106:Immune Sera / Q000494:pharmacology; D007074:Immunoglobulin G / Q000502:physiology; D007959:Lymphocyte Culture Test, Mixed / Q000379:methods; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D013154:Spleen / Q000166:cytology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
D000954:Antigens, Surface; D006028:Glycosphingolipids; D007106:Immune Sera; D007074:Immunoglobulin G; D005677:G(M1) Ganglioside; C018835:asialo GM1 ganglioside; D003165:Complement System Proteins