Neuropilin-1, a myeloid cell-specific protein, is an inhibitor of HIV-1 infectivity

Myeloid lineage cells such as macrophages and dendritic cells (DCs), targeted by HIV-1, are important vehicles for virus dissemination through the body as well as viral reservoirs. Compared to activated lymphocytes, myeloid cells are collectively more resistant to HIV-1 infection. Here we report that NRP-1, encoding transmembrane protein neuropilin-1, is highly expressed in macrophages and DCs but not CD4(+) T cells, serving as an anti-HIV factor to inhibit the infectivity of HIV-1 progeny virions. Silencing NRP 1 enhanced the transmission of HIV-1 in macrophages and DCs significantly and increased the infectivity of the virions produced by these cells. We further demonstrated that NRP-1 was packaged into the progeny virions to inhibit their ability to attach to target cells, thus reducing the infectivity of the virions. These data indicate that NRP-1 is a newly identified antiviral protein highly produced in both macrophages and DCs that inhibit HIV-1 infectivity; thus, NRP-1 may be a novel therapeutic strategy for the treatment of HIV-1 infection.

Automated summary

This study reveals that neuropilin-1 (NRP-1) is highly expressed in macrophages and dendritic cells (DCs) but not CD4(+) T cells. NRP-1 functions as an antiviral protein, inhibiting the infectivity of HIV-1 by reducing the ability of the virions to attach to target cells.