Oligosaccharide components of surface glycoproteins from leukemic lymphocytes of chronic lymphocytic leukemia and non-Hodgkin's lymphoma

Abstract

Oligosaccharide components of surface glycoproteins of leukemic cells have been studied in a group of eight patients with chronic lymphocytic leukemia (CLL) and non-Hodgkin's lymphoma (NHL). Labelled surface glycoproteins were separated by electrophoresis and treated with mild alkaline borohydride, prior to exclusion chromatography on Sephadex G-50. Five peaks were detected, of which peaks I and II consisted largely of N-linked chains and peaks III and IV of O-linked chains. Peak V contained monosaccharides and non-carbohydrate material. On both peripheral blood and lymph node cells of the CLL and nodular poorly differentiated lymphocytic lymphoma (NPDLL) patients studied, glycosylation was altered on leukocyte-common antigen (L-CA) forms of different relative molecular mass ( M r). The ratio of peak II oligosaccharides to those of peaks III and IV in different forms of L-CA correlated closely with M r of the L-CA. Glycosylation of L-CA on cells of two patients with diffuse large cell lymphoma differed from that of the CLL and NPDLL patients, but was also to some extent related to M r. Most of the oligosaccharides on the large sialoglycoprotein were O-linked, only a minor amount of N-linked being detected. Two surface glycoproteins of M r 87 and 83 k differed markedly in their content of O- and N-linked chains. The specific glycosylation patterns described may have a role in control of cell behaviour and disease patterns of leukemia and lymphoma.