Lineage- and differentiation-dependent alterations in the expression of receptors for glycoconjugates (lectins) in different human hematopoietic cell lines and low grade lymphomas.

Important biological functions and cellular recognition phenomena are supposedly governed by specific sugar-protein interactions. Human hematopoietic cell lines offer an excellent model for the study of the expression of endogenous receptors for the carbohydrate part of glycoconjugates with respect to cell lineage and modulation by differentiation. Initially, a panel of fluorescent (neo)glycoproteins was successfully employed to demonstrate cytologically the actual presence of such receptors on different cell lines: the B lymphoblast line, Daudi; the T cell lymphoblastic leukemia line, P12; the multipotent leukemic line, K562 and the promyelocytic line, HL060. Biochemical analyses were performed using affinity chromatography on supports with immobilized lactose and asialofetuin (simple or complex beta-galactosides), melibiose (alpha-galactoside), fucose, N-acetyl-D-galactosamine, maltose (alpha-glucoside), the mannose-rich yeast glycoprotein, mannan, glycopeptides containing sialic acid residues and heparin. Subsequently, sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis was used to detect cell lineage-dependent changes in theses parameters. Differentiation-dependent changes in the expression of receptors with specificity to galactose, N-acetylgalactosamine, maltose and heparin were similarly uncovered upon dimethyl sulfoxide-induced differentiation of HL60 cells. Differences in this type of cellular characteristic were also apparent for lymphoma cells from patients with various histological subtypes of lowgrade lymphomas. This initial description of lineage- and differentiation-dependent differences in various human hematopoietic cell lines and in cells from patients with lowgrade lymphomas suggests that advances in the knowledge of the composition of endogenous sugar receptors (lectins) may aid in understanding aspects of the biological behavior of hematopoietic cells and their related malignancies via participation of sugar-protein (lectin) interactions.