CORRELATION BETWEEN TUMORIGENICITY AND ALTERED GLYCOSYLATION OF A LEUKOCYTE COMMON ANTIGEN IN HUMAN LYMPHOID-CELL LINES

Five human lymphoblastoid cell lines which have become tumorigenic, as judged by transplantability into immunosuppressed mice, were compared with earlier, non-tumorigenic stocks of the same cultures, recovered from liqud nitrogen. Analysis of the cell surface glycorpoteins by SDS-PAGE [sodium dodecylsulfate polyacrylamide gel electrophoresis] electro-transfer to cellulose nitrate and "blotting" with radioiodinated lectins, reveals an increase in the molecular weight of one band from around 190-220 kd, in each case coinciding with the acquisition of the tumorigenic phenotype. Probing the electrotransfers with a monoclonal antibody demonstrates that the altered glycoprotein is a member of the "leukocyte common antigen" family. The increase in molecular weight is due to the addition of carbohydrate residues which are removed by treatment with neuraminidase and endoglycosidase. Screening a larger number of lymphoid cell lines, including those derived from Burkitt''s lymphoma, shows an excellent correlation between tumorigenicity and altered molecular weight of a leukocyte common antigen.