Shared antigen between the myelin-associated glycoprotein (MAG) and a cell line from human T cell leukemia (HSB-2)

HSB-2 is a cell line originated from human T-cell leukemia and its membrane antigen is recognized by anti-HNK-1, a monoclonal antibody against human natural killer (NK) cells. Enzyme linked immunosorbent assay (ELISA) revealed that not only anti-HNK-1 but also rabbit polyclonal and human monoclonal anti-myelin-associated glycoprotein (MAG) antibodies were absorbed by cell homogenate of HSB-2. Molt-4 and K-562 cell lines from human T-cell leukemia and human erythroleukemia did not absorb anti-HNK-1 and the anti-MAG antibodies. On the immunoblot of HSB-2 cell homogenate, two major molecules were stained by anti-HNK-1 and anti-MAG antibodies, while Molt-4 and K-562 were not stained by these antibodies. Comparing molecular weights of the two major molecules with those of MAG and derivative of MAG (dMAG), one is larger than MAG and the other is smaller than dMAG. The molecular weights of the two molecules were approximately 130 kDa and 80 kDa. The shared antigen in HSB-2 is not identical with MAG but a part of the molecule in the cells may be shared with a part of MAG molecule.