title: Biofilm-like extracellular viral assemblies mediate HTLV-1 cell-to-cell transmission at virological synapses.
abstract: Human T cell leukemia virus type 1 (HTLV-1) is a lymphotropic retrovirus whose cell-to-cell transmission requires cell contacts. HTLV-1-infected T lymphocytes form 'virological synapses', but the mechanism of HTLV-1 transmission remains poorly understood. We show here that HTLV-1-infected T lymphocytes transiently store viral particles as carbohydrate-rich extracellular assemblies that are held together and attached to the cell surface by virally-induced extracellular matrix components, including collagen and agrin, and cellular linker proteins, such as tetherin and galectin-3. Extracellular viral assemblies rapidly adhere to other cells upon cell contact, allowing virus spread and infection of target cells. Their removal strongly reduces the ability of HTLV-1-producing cells to infect target cells. Our findings unveil a novel virus transmission mechanism based on the generation of extracellular viral particle assemblies whose structure, composition and function resemble those of bacterial biofilms. HTLV-1 biofilm-like structures represent a major route for virus transmission from cell to cell.
authors.affiliation: Institut Pasteur, Unité de Biologie Cellulaire des Lymphocytes, Centre National de Recherche Scientifique (CNRS), Unité de Recherche Associée 1961, Paris, France.
authors.forename: Ana-Monica
authors.initials: AM
authors.lastname: Pais-Correia
authors.forename: Martin
authors.initials: M
authors.lastname: Sachse
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Guadagnini
authors.forename: Valentina
authors.initials: V
authors.lastname: Robbiati
authors.forename: Rémi
authors.initials: R
authors.lastname: Lasserre
authors.forename: Antoine
authors.initials: A
authors.lastname: Gessain
authors.forename: Olivier
authors.initials: O
authors.lastname: Gout
authors.forename: Andrés
authors.initials: A
authors.lastname: Alcover
authors.forename: Maria-Isabel
authors.initials: MI
authors.lastname: Thoulouze
mesh_terms: D018441:Biofilms; D015496:CD4-Positive T-Lymphocytes / Q000821:virology*; D003208:Concanavalin A; D005109:Extracellular Matrix / Q000821:virology*; D015686:Gene Products, env / Q000378:metabolism; D015490:HTLV-I Infections / Q000635:transmission* / Q000821:virology; D015368:Human T-lymphotropic virus 1 / Q000472:pathogenicity / Q000502:physiology*; D006801:Humans; D046529:Microscopy, Electron, Transmission; D019065:Virus Assembly / Q000502:physiology; D053585:Virus Attachment; D053586:Virus Internalization
chemical_list: D015686:Gene Products, env; D003208:Concanavalin A