A high-resolution technique has been used to study differentiation-related and leukemia-associated glycoproteins. Cells are labeled with the membrane-impermeable probe sulfo-N-hydroxysuccinimidyl-biotin. Nonionic detergent extracts are subjected to affinity chromatography on a number of immobilized lectins and after polyacrylamide gel electrophoresis in sodium dodecyl sulfate (SDS-PAGE) and western transfer, the biotin-labeled glycoproteins are visualized by using avidin-horseradish peroxidase and 4-chloronaphthol. With the aid of the lectins concanavalin A, Dolichos hiyouros agglutinin, Lens culinaris hemagglutinin, peanut agglutinin, pokeweed mitogen, Ricinus communus agglutinin I, soybean agglutinin, Ulex europeus agglutinin I (UEA), and wheat germ agglutinin, each purifies different glycoprotein subsets from the same cell type. Mature cells of distinct hematopoietic lineages differ considerably in their cell surface glycoprotein patterns.
This technique was used to analyze the glycoproteins of human leukemia cells before and after the induction of differentiation. K562 cells differentiated along different lineages after treatment with phorbol 12-myristate 13-acetate, sodium bu- tyrate, dimethyl sulfoxide, or hemin. Limited specific alterations were observed with a number of lectins when K562 erythroleukemia cells were induced to differentiate. Among these, a number of bands were identified that were either lost or appeared after induction of differentiation with all four agents. In contrast, the glycoproteins bound by UEA were drastically diminished after induction of differentiation, and the remaining UEA-bound glycoproteins bore little resemblance to those of the cells before treatment. This high-resolution technique may be useful as a general method for the examination of cell surface glycoprotein differences. Once specific glycoprotein alterations are detected, lectin affinity chromatography and SDS-PAGE allow purification of antigens for the production of monoclonal antibodies.