Heterogenicity and specificity of tumor associated antigens (TAA) and fetal antigens (FA) as detected by 51Cr leukocyte adherence inhibition test and electrophoretic mobility test in mouse sarcomas

Soluble extracts (3 M KCl) were prepared from tumor tissue and mouse fetuses. After separation on ULTROGEL AcA 34 single fractions of these antigens were incubated with spleen cells of tumor bearing and pregnant mice, resp. and the response was detected by 51Cr leukocyte adherence inhibition and/or electrophoretic mobility techniques. There was only a partial correlation between the results of both test systems. Different antigen activities were found in three regions of molecular weight: P1 (200,000-250,000), P2 (120,000-160,000) and P3 (50,000-60,000). Individual specific activity was detected in P2 fractions of TAA whereas P3 fractions of TAA and FA as well as P1 fraction of FA revealed cross reactivities. Pregnant specificity was localized in P2 fraction of FA. (author)