Tumor-DNA Based Vaccines Fail to Induce Autoimmune Disease in Mice

Allogeneic cellular cancer vaccines that express tumor antigens specified by tumor-DNA have been found to be effective in the treatment of mice with intracerebral breast cancer, a metastasis model system. The vaccines were prepared by the transfer of genomic DNA from a spontaneously arising adenocarcinoma of the mammary gland into a mouse fibroblast cell line (LM). The immunity in tumor-bearing mice treated by immunization with the DNA-based vaccines was specific for the type of tumor from which the DNA was obtained. It was driven mainly by CD8+ T-cells. Here, we present data indicating that animals receiving the therapeutic vaccines failed to exhibit signs of autoimmunity, as indicated by an examination of various H/E stained organs and tissues including brain for infiltrating inflammatory cells and by the absence of serum anti-nuclear antibody (ANA) in the immunized mice. In addition, tumors derived from the vaccine itself failed to develop in immune-competent tumor-free mice injected with the non-irradiated allogeneic vaccines alone.