Alteration of immunogenicity of xenogenized tumor cells in syngeneic rats by the immune responses to virus-associated antigens produced on immunizing cells.
A strong transplantation resistance to a fibrosarcoma (KMT-17) is induced in syngeneic Wistar King Aptekman/Hok rats after a single s.c. immunization with Friend virus-infected (xenogenized) viable KMT-17 cells. The resistance induced by the repeated immunizations with irradiated Friend virus-infected KMT-17 cells, however, was unexpectedly weaker when compared with that induced by irradiated KMT-17 cells. The immunogenicity of tumor-associated antigen on xenogenized Friend virus-infected KMT-17 cells was correlated with their shortened survival time in the peritoneal cavity after i.p. inoculation, especially in rats preimmunized with xenogenized tumor cells. Furthermore, xenogenized tumor cells producing a medium amount of virus-associated antigen (VAA) but not those producing a large amont of VAA showed an augmented immunogenicity even in normal rats. On the other hand, the tumor-associated antigen immunogenicity was augmented by immunization with xenogenized tumor cells which expressed a relatively small amount of VAA in rats presensitized with VAA. These findings indicate that the immunogenicity of xenogenized tumor cells is augmented by the middle-grade immune responses to VAA produced on xenogenized tumor cells.
D000818:Animals; D000951:Antigens, Neoplasm / Q000276:immunology; D000956:Antigens, Viral / Q000276:immunology*; D005354:Fibrosarcoma / Q000139:chemically induced / Q000276:immunology*; D005622:Friend murine leukemia virus / Q000276:immunology*; D006084:Graft Rejection; D007114:Immunization; D007117:Immunization, Secondary; D008748:Methylcholanthrene; D009368:Neoplasm Transplantation; D051381:Rats; D011919:Rats, Inbred Strains; D012513:Sarcoma, Experimental / Q000276:immunology
D000951:Antigens, Neoplasm; D000956:Antigens, Viral; D008748:Methylcholanthrene