EXPRESSION OF GLYCOSYLATED RECOMBINANT HUMAN MYELIN-ASSOCIATED GLYCOPROTEIN ON A NEUROBLASTOMA CELL-LINE AND ITS REACTIVITY WITH HNK-1 BUT NOT HUMAN ANTI-MAG ANTIBODIES

A correctly glycosylated myelin-associated glycoprotein (MAG) must exp ress the carbohydrate epitope HNK-1, which is the target antigen for I gM antibodies in some patients with neuropathy. We transfected a human MAG cDNA clone into the neuroblastoma cell line SK-N-SH and verified by immunoblot the expression of the HNK-1 epitope on the recombinant m olecule. By the same method and by indirect immunofluorescence we did not find any reactivity of human anti-MAG IgM antibodies with glycosyl ated recombinant MAG and transfected neuroblastoma cells. These findin gs suggest that the mere presence of the HNK-1 epitope is probably not sufficient for MAG to be recognized by human antibodies and that othe r factors such as the concentration or fine structure of this epitope in MAG, which mostly depend on the cellular context, may be also criti cal for this reactivity. (C) 1998 Elsevier Science Ireland Ltd.