Therefore, we have characterized the immuno-modulatory properties of P1, a conserved peptide from the HIV-1 glycoprotein gp41 we have previously shown to be a powerful vaccine antigen providing full protection against mucosal HIV infection following intra-nasal immunization (8) and determined its stimulatory activities in human nasal epithelial cells and dendritic cells, the two major targets of nasal vaccination. Here, ART4 is linked to HIV infectious disease.