Partial characterization of nervous system specific cell surface antigen(s) NS-2

Partial biochemical characterization of several neural tissue specific antigens isolated from a murine glioblastoma cell line was accomplished by means of radioiodination of intact cells followed by immunoprecipitation of the cell lysate with a rabbit serum specific for neural tissue antigens. Polyacrylamide gel electrophoresis of the immunoprecipitate in sodium dodecyl sulfate resolved the labeled antigens into several major components: two proteins (or glycoproteins) having apparent m.w.'s of 84,000 and 120,000 and lipid associated components which may be heterogeneous. The protein and lipid associated components apparently possess independent antigenicity because after chloroformmethanol extraction the protein components can be immunoprecipitated from the aqueous phase and the lipid associated component can be immunoprecipitated from the organic phase. Despite their independent antigenicity it is not known whether the components may be noncovalently associated on the cell surface. Although some of these antigens can be isolated from brain or glioma cells (a related tumor), none can be demonstrated in lymphoid tissues or C1300 neuroblastoma cells using identical methods. Therefore, these studies confirm the authors' previous findings concerning the specificity of the anti NS 2 antiserum by using cytotoxicity tests.