1997 Volume 22 Issue 5 Pages 511-516
To investigate neuron-specific antigens, hybridoma cells were produced between mouse spleen cells immunized with human neuroblastoma cells (IMR-32) and mouse myeloma cells. 247 hybridoma clones were harvested and one of them was further cultured for recloning. Eventually, one hybridoma clone was obtained and its antibody was designated N-A8. The characteristics of this antibody were determined by immunostaining and flow cytometry. First, the antibody recognized the surface antigens of IMR-32 cells. Second, unexpectedly, N-A8 was reactive not only with human neuroblastoma cell lines but also with human lung cancer cell lines. As analyzed by immunoprecipitation method and SDS-PAGE, the molecular size of the antigen recognized by N-A8 was 210 kDa. The antigen was then purified by affinity chromatography and identified as neural adhesion molecule LI by amino acid sequence analysis. By the present investigation, it was clearly demonstrated that LI is expressed in human lung cancer cells.