GANGLIOSIDE CHARACTERIZATION OF A CELL-LINE DISPLAYING MOTOR NEURON-LIKE PHENOTYPE - GM2 AS A POSSIBLE MAJOR GANGLIOSIDE IN MOTOR-NEURONS

We have examined ganglioside compositions and the presence of sulfated glucuronyl glycolipids of immortalized motor neuron-like cell lines, neuroblastoma-spinal cord (NSC) hybrid cell lines established by fusin g mouse neuroblastoma N18TG2 with motor neuron-enriched embryonic spin al cord cells. Among NSC cell lines, only NSC-34 aggregates acetylchol ine receptors on co-cultured myotube and expresses a receptor for S-la minin, a neuromuscular junction specific basal lamina protein. GM2, wh ich is only a minor ganglioside component of CNS, was the major compon ent in NSC-34 occupying almost 75% of total gangliosides, whereas GD1a and GM3 were major species in the parental N18TG2, which had only 8.5 % GM2. These results indicated that NSC lines have unique ganglioside pattern that is distinctive from other nervous tissues, and this patte rn, especially that of NSC-34 cells, might reflect the characteristics of mouse spinal motor neuron gangliosides. Sulfated glucuronyl paragl oboside was demonstrated to be present in N18TG2, however, it could no t be detected in either of NSC cell lines. Even though the pathogenesi s of amyotrophic lateral sclerosis remains unknown, autoimmunological participation has been suggested. Because high-titered antibody agains t GM2 has been observed in a patient with amyotrophic lateral sclerosi s-like disease, GM2 which is possibly expressed on the surface of moto r neurons might serve as a potential target antigen in this disorder.