Xenovaccinotherapy for melanoma in experimental studies

Vaccination of melanoma B16-bearing C57BL6-mice with human Bro melanoma cell lysate resulted in the increase in serum interleukin-4 (IL-4) concentration and tumor infiltration preferably by neutrophils. At the same time, vaccination of tumor-bearing mice with melanoma B16 cell lysate led to the increase in serum interferon-gamma (IF-gamma) and tumor infiltration by neutrophils and lymphocytes. Histological analysis showed a high rate of tumor cell death in both groups of vaccinated animals. Nevertheless, only xenogenic but not syngenic vaccination associated with life prolongation of tumor-bearing mice. Thus, the data obtained point out the importance of xenovaccination of T-helper-2-mediated immune responses in the mechanism of anti-tumor effect.