The human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein gp120 is a vaccine immunogen that has been studied extensively. To enhance the immune response of cells against HIV-1 gp120, we tested the coexpression of gp120N with interferon-gamma (IFN-gamma) as an immune adjuvant. Two recombinant prokaryotic plasmids were constructed: the pET44b-HIV-1-gp120N plasmid construct carried the HIV-1 gp120N gene (pET44-gp120N), whereas the pET44b-HIV-1-gp120N-IFN-gamma plasmid construct carried a fusion gp120N-IFN-gamma gene (pET44b-gp120N-IFN-gamma). Target protein expression was achieved in E. coli BL21 (DE3) cells by chemical induction. To test the immunological activity of the proteins, mice were injected with a control, gp120N, or the fusion gp120N-IFN-gamma protein. The serum and spleen cells of the mice were collected for immunological detection. Results showed that specific T lymphocyte proliferation and the expression of the Th1-type cytokines (IL-2 and IFN-gamma) were higher in the gp120N-IFN-gamma group than the other two groups (P < 0.05). No difference was observed in the expression levels of the Th2-type cytokines (IL-4 and IL-10; P > 0.05). These results suggest that IFN-gamma plays a prominent role as an immune adjuvant when coexpressed with HIV-1 gp120N. IFN-gamma enhances the specific cell immune response of mice against HIV-1 gp120.
(c) 2009 Wiley-Liss, Inc.