The ectodomain sheddase ADAM10 restricts HIV-1 propagation and is counteracted by Nef.

HIV-1 Nef enhances virus propagation by down-regulating CD4 and SERINC5. However, recent evidence points to the existence of an additional Nef-sensitive restriction mechanism. We now show that Nef suppresses the aberrant cleavage of HIV-1 gp41 by ADAM10, a virion-associated cellular ectodomain sheddase, and thus increases the amount of HIV-1 envelope glycoprotein (Env) on virions. Additionally, Nef inhibits the shedding of at least some cellular ADAM10 substrates, resulting in their accumulation on HIV-1 virions. Whereas Nef+ HIV-1 replicated only marginally better in the absence of ADAM10, the propagation of Nef- HIV-1 was notably rescued in ADAM10- T cell lines. Crucially, Nef- HIV-1 also benefited from the absence of ADAM10 in primary CD4+ T cells. Collectively, our results indicate that ADAM10 negatively affects both laboratory-adapted and primary HIV-1 strains by shedding the ectodomains of viral and cellular transmembrane proteins from virions and that Nef rescues virus replication by counteracting ADAM10.