Transformation by simian virus 40 of spleen cells from a hyperimmune rabbit: demonstration of production of specific antibody to the immunizing antigen

Extracts of spleen cells obtained from a rabbit hyperimmunized with Type III pneumococcal vaccine and transformed with simian virus 40, were subjected to agarose gel electrophoresis in the presence of an [¹²⁵I]S3 polysaccharide protein conjugate. Binding of radioactivity in the gamma globulin region was observed. Extracts and media obtained from labeled cell cultures contained a protein that bound to an S3, but not to an S8 or inactivated S3 immunoadsorbent. After elution, the bound protein showed a single band on isoelectric focusing which corresponded in isoelectric point to one of the serum anti S3 antibodies of the donor rabbit. These observations strongly suggest that a normal, committed lymphoid cell may be brought into continuous culture by virus transformation and yet retain its ability to synthesize specific antibody.