Innate immunity and intracellular trafficking : insights for novel anti-HIV-1 therapeutics

It is now evident that host cells have evolved a remarkable variety of antiretroviral activities to defend themselves against viral invaders and in return viruses have developed ingenious ways to circumvent these defences and, in some cases, actually hijack cellular proteins in order to facilitate their replication. Study of this cat and mouse interplay between viruses and their host cells throughout evolution has lead to the identification of some of the most sophisticated antiviral strategies that mammals have developed to prevent viral infection. Recently, a wave of publications has significantly enhanced our understanding of the relationship between human immunodeficiency virus type 1 (HIV-1) and its host, including: 1) the HIV-1 protein Vif and its interaction with host cell nucleic acid editing enzymes; 2) the host cell restrictive factors that provide protection against retroviral infection, such as TRIM5; and 3) the late domains of retroviruses and their relationship with the host cell vacuolar protein sorting pathway. The focus of this review is to provide an up-to-date account of these important areas of HIV-1 research and highlight how some of these new discoveries can potentially be exploited for the development of novel anti-retroviral therapeutics.