This is a new technology which involves the direct injection of plasmid DNA which encodes cancer antigens into the hosts muscle tissue. DNA vaccines are particularly exciting because they increase both a humoral and strong CTL response. Recent tests done on mice with skin cancer injected with human protein DNA, targeting gp75 protein shared by mice tumor cells and the human DNA. The DNA differed just enough from the mouse counterpart to be able to induce a strong immune response in the mice. The response was so strong that both the foreign DNA and the tumor cells of the mice were attacked. The human DNA was thus able to induce an autoimmune response which prevented the spreading of the tumor. Memorial Sloan-Kettering Cancer Center plans on beginning clinical trials using DNA from mice in cancer patients next year.