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In vitro derived dendritic cells trans-infect CD4 T cells primarily with surface-bound HIV-1 virions.

ABSTRACT: In the prevailing model of HIV-1 trans-infection, dendritic cells (DCs) capture and internalize intact virions and transfer these virions to interacting T cells at the virological synapse. Here, we show that HIV-1 virions transmitted in trans from in vitro derived DCs to T cells principally originate from the surface of DCs. Selective neutralization of surface-bound virions abrogated trans-infection by monocyte-derived DCs and CD34-derived Langerhans cells. Under conditions mimicking antigen recognition by the interacting T cells, most transferred virions still derived from the cell surface, although a few were transferred from an internal compartment. Our findings suggest that attachment inhibitors could neutralize trans-infection of T cells by DCs in vivo.

SUBMITTER: Cavrois M

PROVIDER: S-EPMC1779297 | biostudies-literature |

REPOSITORIES: biostudies-literature

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