Development of TNFSF as molecular adjuvants for ALVAC HIV-1 vaccines

A phase III clinical trial finished in Thailand recently showed that an ALVAC HIV-1 vaccine prime-gp120 protein boost vaccination regimen could modestly protect persons from HIV-1 infection, demonstrating that development of an effective and safe HIV-1 preventive vaccine is possible. ALVAC HIV-1 vaccines are candidate HIV-1 vaccines based on canarypox vectors. Previous clinical trials proved that ALVAC HIV-1 vaccines were safe but weak in immunogenicity when used in human subjects. We have been exploring to use tumor necrosis factor superfamily (TNFSF) members as adjuvants to enhance the immunogenicity of ALVAC HIV-1 vaccines. In this commentary, we will summarize our findings in using two TNFSF molecules, CD40L and OX40L, as adjuvants for an ALVAC HIV-1 vaccine in mouse model. We will also briefly discuss the challenges and prospects of using TNFSF molecules as adjuvants for HIV-1 vaccines in humans.