Serologically detectable MHC and tumor-associated antigens on B16 melanoma variants and humoral immunity in mice bearing these tumors

We compared the expression of serologically detectable MHC and tumor-associated antigens on low and high metastasis variants of B16 melanoma tumor. Complement-dependent cytotoxicity, radioimmunobinding, and quantitative absorption assays showed that with respect to both types of antigens the low metastasis variant B16-F1 expressed a higher serologically detectable antigenicity than B16-F10, its high metastasis counterpart. A reverse situation existed in terms of in vivo immunogenicity of these metastasis variants. Sera from C57BL/6 mice bearing locally growing B16-F10 tumors had a higher binding activity to B16 cells than sera from B16-F1 bearers. Accordingly, in vivo propagating B16-F10 tumors had a higher content of tumor-associated Ig than B16-F1 tumors.