ABSTRACT
Extracellular vesicles (EVs) are biomolecule carriers for intercellular communication in health and disease. Nef is a HIV virulence factor that is released from cells within EVs and is present in plasma EVs of HIV-1 infected individuals. We performed a quantitative proteomic analysis to fully characterize the Nef-induced changes in protein composition of T cell-derived EVs and identify novel host targets of HIV. Several proteins with well-described roles in infection or not previously associated with HIV pathogenesis were specifically modulated by Nef in EVs. Among the downregulated proteins are the interferon-induced transmembrane 1, 2, and 3 (IFITM1-3) proteins, broad-spectrum antiviral factors known to be cell-to-cell transferable by EVs. We demonstrate that Nef depletes IFITM1-3 from EVs by excluding these proteins from the plasma membrane and lipid rafts, which are sites of EVs biogenesis in T cells. Our data establish Nef as a modulator of EVs' global protein content and as an HIV factor that antagonizes IFITMs.
Subject(s)
Extracellular Vesicles , HIV Infections , HIV-1 , Humans , T-Lymphocytes , Proteome/metabolism , Proteomics , Extracellular Vesicles/metabolism , Interferons/metabolism , HIV Infections/metabolism , Antiviral Agents/metabolismABSTRACT
Recent seroprevalence studies in animals detected Rocio virus in regions of Brazil, indicating risk for re-emergence of this pathogen. We identified Rocio virus RNA in samples from 2 human patients for whom dengue fever was clinically suspected but ruled out by laboratory findings. Testing for infrequent flavivirus infections should expedite diagnoses.