
<ArticleTitle>Nef is required for efficient HIV-1 replication in cocultures of dendritic cells and lymphocytes.</ArticleTitle>
<AbstractText>Dendritic cells (DCs) are thought to play a crucial role in the pathogenesis of HIV-1 infection. DCs are believed to transport virus particles to lymph nodes before transfer to <prot>CD4</prot>(+) lymphocytes. We have investigated the role of <prot>Nef</prot> in these processes. HIV-1 replication was examined in human immature DC-lymphocyte cocultures and in DCs or lymphocytes separately. Using various R5-tropic and X4-tropic HIV-1 strains and their <prot>nef</prot>-deleted (Deltanef) counterparts, we show that <prot>Nef</prot> is required for optimal viral replication in immature DC-T cells clusters and in T lymphocytes. <prot>Nef</prot> exerts only a marginal role on viral replication in immature DCs alone as well as on virion capture by DCs, long-term intracellular accumulation and transmission of X4 strains to lymphocytes. We also show that wild-type and Deltanef virions are similarly processed for MHC-I restricted exogenous presentation by DCs. Taken together, these results help explain how HIV-1 <prot>Nef</prot> may affect viral spread and immune responses in the infected host.</AbstractText>
