The use of xenogenic cancer/testis antigens forinduction of antitumor reactions

Testicular antigens (TAGs) are normally expressed only by cells of testicular and placental tissues. Human immune system is tolerant to TAG, but if the integrity of the testicular membranes is disrupted, these antigens, entering the bloodstream, induce autoimmune reactions for eliminating them from the body. In malignancy, TAGs begin to be expressed by tumor cells of the liver, breast, pancreas, intestine, and lung. Immunological recognition of these AGs leads to autoimmune reactions against these AGs, i.e. antitumor reactions in the body. We used xenogenic TAGs derived from ram testis to increase TAG immunogenicity. The use of ram TAGs is justified by the fact that TAGs are evolutionarily conserved molecules and there is a high degree of homology between human and animal TAGs. The purpose of the study was to evaluate the lifespan of tumor-bearing mice and parameters of cellular immunity in various options for immunizing mice with ram TAGs. Material and Methods. C57BL/6 mice were used. The efficacy of therapeutic or prophylactic vaccination with xenogenic TAGs was studied by changing lifespan of B16 and LLC tumor-bearing mice. Formation of immune responses was evaluated by proliferative ability of splenocytes to respond to vaccination and control AGs and by their production of IFN-gamma and IL-10.