Boosting Tat DNA vaccine with Tat protein stimulates strong cellular and humoral immune responses in mice

Abstract

The aim of the present study was to evaluate the efficacy of a novel DNA priming-protein boosting regimen in simultaneous enhancing humoral and cellular immunogenicity of the HIV-1-Tat-based candidate vaccines in mice. The experimental BALB/ c mice were successfully immunized with the HIV-1-Tat DNA vaccine and boosted with the corresponding protein vaccine over a two-week interval and the elicitation of cellular and humoral immune responses were simultaneously assessed. The results showed that the prime-boost immunization has significantly given rise to lymphocyte proliferation and CTL responses, as well as the levels of both IgG and IgG antibodies compared to the other candidate vaccines. The results of the Th polarization also revealed that the Th1: Th2 indexes in the mice vaccinated with the HIV-1 Tat protein, Tat DNA, and the prime-boost vaccines were 1.03, 1.19, and 1.25, respectively. The results suggest that co-administration of the HIV-1-Tat DNA with the corresponding protein may serve as a potential formulation for enhancing of Tat vaccineinduced immunity and has measurable effects on shaping vaccines' induced Th polarization.

The Tat Protein of HIV-1 Prevents the Loss of HSV-Specific Memory Adaptive Responses and Favors the Control of Viral Reactivation

“…The difference in disease symptoms was particularly evident between 7 and 9 days after challenge before the disease signs spontaneously healed in both groups (Figure 1C). they are effectively induced after administration of the Tat protein in humans [46][47][48] and animals [49][50][51]. Consistent with this, 100% of Tat-treated mice displayed anti-Tat IgG at both 60 and 108 days p.i.…”

“…Instead, we asked whether anti-Tat specific antibodies (Ab) could recognize and cross-react with HSV-1. Although anti-Tat Ab are detectable in only a fraction of HIV-infected individuals [ 44 , 45 ], they are effectively induced after administration of the Tat protein in humans [ 46 , 47 , 48 ] and animals [ 49 , 50 , 51 ]. Consistent with this, 100% of Tat-treated mice displayed anti-Tat IgG at both 60 and 108 days p.i.…”