Sequential change of carbohydrate antigen associated with differentiation of murine leukemia cells: i-I antigenic conversion and shifting of glycolipid synthesis.
Cell surface carbohydrate antigens and their metabolism were investigated during the course of differentiation of murine cultured leukemia cells (M1) into macrophage-like cells. The major glycolipids in undifferentiated M1 cells were of the ganglio series, with a small amount of lacto-series glycolipids. A novel branched structure was found as a tetraosylceramide of M1- cells. Upon differentiation, synthesis of lacto-series glycolipids was significantly enhanced and synthesis of globo-series glycolipids was newly induced but the ganglio-series synthesis was much reduced. Undifferentiated cells expressed only i antigen (i+I-Pk-); differentiated macrophage-like cells became I-antigen dominant and Pk-antigen positive (i+/-I+Pk+). The changes proceeded in two sequential steps: (i) an enhancement of lacto-series glycolipid synthesis associated with the conversion of i antigen to I antigen, and (ii) subsequent induction of globo-series glycolipid synthesis accompanied by the appearance of Pk antigen. The experimental system offers a clue for studies on the process of branching (i-to-I conversion) as well as the biological significance of three major glycolipids (globo-, lacto-, and ganglio-series) as markers of cell differentiation.
D000818:Animals; D002240:Carbohydrate Sequence; D002454:Cell Differentiation; D002460:Cell Line; D005732:Gangliosides / Q000276:immunology; D006017:Glycolipids / Q000096:biosynthesis / Q000276:immunology*; D007048:I Blood-Group System; D007942:Leukemia, Experimental / Q000276:immunology*; D008264:Macrophages / Q000166:cytology; D051379:Mice; D010127:P Blood-Group System
D005732:Gangliosides; D006017:Glycolipids; D007048:I Blood-Group System; D010127:P Blood-Group System