Background
The immunogenicity of current human immunodeficiency virus-1 (HIV-1) canarypox vaccines is weak and needs to be improved. Ligation of OX40 (CD134), a member of tumor necrosis factor receptor superfamily (TNFRSF), by its ligand OX40L (CD252), a tumor necrosis factor superfamily (TNFSF) molecule, has been demonstrated to provide a pivotal costimulatory signal to enhance CD4 T cell help of humoral and cytotoxic T cell immune responses. The present study examined whether an OX40L expressing vector could boost the immunogenicity of the HIV-1 canarypox vaccine, vCP1452, in mice.