CD8A and neoplasm: A major benefit of this model is that it prevents HPV18E6/E7 antigen from presenting via murine MHC class I, but rather the antigen will present via human MHC class I. Furthermore, HPV18 E6/E7-expressing tumor cell line lack of murine MHC class I restricted CD8 + T cell epitopes can be generated from these spontaneously established tumors.