VaxGen, Inc.

We investigated effects of vaccination with AIDSVAX B/E HIV-1 candidate vaccine on blood and seminal plasma HIV-1 RNA viral loads (BVL and SVL, respectively) in vaccine recipients (VRs) and placebo recipients (PRs) who acquired infection.

Linear mixed models were fitted for repeated measurements of BVL. Generalized estimating equations were used to assess the difference in SVL detectability between VRs and PRs.

A total of 196 participants became HIV-1 infected during the trial. Thirty-two (16%) became infected with HIV-1 subtype B and 164 (84%) with HIV-1 subtype CRF01_AE. Per protocol-specified analysis, there were no differences in BVL levels between VRs and PRs. When stratified by HIV-1-infecting subtype, vaccination with AIDSVAX B/E was initially associated with higher BVL among HIV-1 CRF01_AE-infected VRs compared with HIV-1 CRF01_AE-infected PRs; however, this difference did not persist over time. HIV-1 subtype B-infected VRs had slightly higher BVL levels and were more likely to have detectable SVL during the follow-up period than HIV-1 subtype B-infected PRs.

Subtle differences in BVL and SVL were detected between VRs and PRs. These results may help to further understand the dynamics between HIV-1 vaccination, HIV-1-infecting subtypes, and subsequent viral expression in different body compartments.

This study examined the effect of an HIV vaccine on mucosal innate factor expression. Serum, gingival fluid, and genital mucosal secretions were collected from high-risk women and men enrolled in an HIV-1 efficacy vaccine trial and from low-risk women and men. Samples were tested by standard ELISA for lactoferrin, myeloid-related protein-8/14, and secretory leukocyte protease inhibitor. No consistent significant changes in innate factor levels were found in serum or secretions from vaccinees compared to placebo recipients or from high-risk compared to low-risk individuals. Because of the importance of innate immunity in host defense, evaluation of the mucosal innate immune system should be included in future HIV prevention trials.