The normal sera of several mouse strains contained cytotoxic activity toward lymphocytes treated with neuraminidase (Nase) but not to untreated cells. The greatest cytotoxic activity was in C3H/HeJ mice. CBA/J and AKR/J mice also had high levels. In C57BL/6J mice, there was no cytotoxic activity toward Nase treated lymphocytes. This cytotoxic activity (probably antibody) was complement dependent and stable at 56°C for 30 min, but was inactivated by heating to 80°C for 30 min. Nase treated C3H/HeJ and C57BL/6J cells contained equal amounts of this 'hidden' antigen, as determined by absorption studies. Untreated cells contained no detectable antigen. These natural antibodies to a 'cryptic' antigen exposed by Nase treatment were the basis of a theory to explain the increased immunogenicity of Nase treated cells.
ASJC Scopus subject areas
- Cancer Research