ASSOCIATION OF THE GPI-ANCHORED LEUKOCYTE SURFACE GLYCOPROTEINS WITH GANGLIOSIDE GM3

The major glycolipid co-immunopurifying with the glycosylphosphatidyli nositol-anchored leucocyte surface glycoprotein CD59 from detergent ly sates of human T cell lines HPB ALL, Jurkat and myeloid line HL-60 was identified as the glycosphingolipid GM3. Monoclonal antibodies to GM3 immunoprecipitated the same large detergent-resistant, protein-tyrosi ne kinase containing ''GPI-complexes'' as antibodies to several GPI-an chored proteins. Therefore GM3 is another component of these large mem brane complexes potentially involved in signalling through GPI-anchore d receptors or through some glycolipids. (C) 1994 Academic Press, Inc.