Recruitment of HIV and its receptors to dendritic cell-T cell junctions.

Monocyte-derived dendritic cells (MDDCs) can efficiently bind and transfer HIV infectivity without themselves becoming infected. Using live-cell microscopy, we found that HIV was recruited to sites of cell contact in MDDCs. Analysis of conjugates between MDDCs and T cells revealed that, in the absence of antigen-specific signaling, the HIV receptors CD4, CCR5, and CXCR4 on the T cell were recruited to the interface while the MDDCs concentrated HIV to the same region. We propose that contact between dendritic cells and T cells facilitates transmission of HIV by locally concentrating virus, receptor, and coreceptor during the formation of an infectious synapse.