Enhanced HIV-1 envelope-tumor protection by a recombinant vaccinia virus expressing anchored HIV-1 gp120 lacking gp41

A recombinant vaccinia virus (rvv) expressing, human immunodeficiency virus type 1 (HIV-1) external envelope glycoprotein, gp120, fused to a non-cleavable transmembrane protein, vvE13, elicited protection against a tumor cell line expressing HIV-1 full length envelope glycoprotein, gp160, in mice. Mice vaccinated with vvE13 exhibited a decreased incidence of tumor development and significantly smaller tumors in comparison to mice vaccinated with rvv gp160, vvE1, or a thymidine kinase minus (TK-) rvv, vSC11, or phosphate-buffered saline (PBS) injected controls. vvE13 and vvE1 also delayed tumor development, compared to vSC11 and PBS-injected controls; however, a statistical correlation could not be demonstrated due to the development of tumors in so few animals. Specificity toward HIV-1 envelope glycoprotein, was shown, since HIV-1 envelope-tumor prevention (incidence for vvE13 and size for vvE1 and vvE13 and delay for vvE1 and vvE13) was statistically superior with HIV-1 envelope expressing tumors compared to parenteral tumors. The vvE13 recombinant vaccinia virus expressing the HIV-1 envelope glycoprotein gp120 fused to a non-cleavable transmembrane protein elicits superior protection against tumors expressing the gp160 envelope glycoprotein, as compared to vvE1 expressing gp160.