Toufu Zhu's laboratory is currently focussing on the pathogenesis of HIV infection, with particular emphasis on the mechanisms of HIV-1 persistence at extraordinarily low levels in vivo. We are devoting considerable effort toward identifying HIV-1 strains which are defective or attenuated, and human genes that protect against and/or control HIV-1 infection. We also have intense interest in defining the role of CD14+ monocytes in HIV-1 transmission as well as during the very early course of HIV-1 infection. The above studies should assist in developing new therapeutic strategies and HIV-1 vaccine or strategies to enhance vaccine efficacy.