Abstract
Surface glycoproteins of normal human B lymphocytes, B blasts and various types of lymphoid cell lines were labelled by the galactose oxidase‐tritiated sodium borohydride method. The labelled glycoproteins were separated by polyacryUmide slab gel electrophoresis in the presence of sodium dodecy! sulfate and visualized by modified autoradiography (fluorography). The battery of examined hematopoietic cell lines included Epstein‐Barr virus (EBV) carrying lines of proven malignant origin (Burkitt's lymphoma) and presumed non‐neoplastic origin (lymphoblastoid cell lines), and EBV‐genome‐negative lymphocytic lymphoma, histiocytic lymphoma, myeloma and myeloid leukemia lines. The presence of possible EBV‐associated surface glycoproteins, detectable by the labelling method, was studied by use of two EBV‐negative cell lines (BJAB and Ramos) and their EBV‐converted sublines. The six Burkitt lymphoma and three lymphocytic lymphoma lines had all the basic surface glycoprotein pattern of resting B cells and, in addition to individually distinct bands, two characteristic pairs of glycoproteins sf apparent molecular weights of 87,000/85,000 and 71,000/69,OOO. These glycoproteins were not detected on the normal B celts, B blasts or non‐neoplastic lymphoblastoid lines. Neither were they found on the other types of neoptastic line. No consistent difference in the surface glycoprotein patterns was detected between the EBV‐genome‐negative and EBV‐con‐verted BJAB and Ramos sublines. The glycoprotein pattern of the six lymphoblastoid lines resembled that of the B blasts. The histiocytic lymphoma, myeloma and leukemia lines all had distinct patterns. These results confirm that the Burkitt's lymphoma and the lymphoblastoid cell lines represent two biologically distinct EBV‐carrying B lymphoid celts and that the galactose oxidase NaB[^3^H]~4~ surface labelling technique can be used as a reliable molecular mapping method to distinguish between these two and other types of lymphoid cell lines.