Autophagy in HIV-1 infection. Left) HIV-1 replication requires early autophagic events for its replication, perhaps because the autophagosomal membrane provides a scaffold for virion assembly. Incomplete, or fully formed virions that enter the cell via endocytosis, could be degraded by the autophagy (xenophagy) pathway. However, HIV-1 can inhibit the late stage of autophagy to avoid the digestion of virions within autolysosomes. Right) Autophagy is a crucial component of innate and adaptive immune responses to HIV-1 infection. Autophagy is required for the TLR7-mediated signaling of interferon-alpha (IFN-α) production by plasmacytoid dendritic cells (innate immunity) in response to HIV. Autophagy also contributes to proteolytic processing for the presentation of HIV-1 peptides in the context of MHC class II (adaptive immunity).