Biofilm-like extracellular viral assemblies mediate HTLV-1 cell-to-cell transmission at virological synapses.
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.
Pais-Correia
Ana-Monica
AM
Institut Pasteur, Unité de Biologie Cellulaire des Lymphocytes, Centre National de Recherche Scientifique (CNRS), Unité de Recherche Associée 1961, Paris, France.
Sachse
Martin
M
Guadagnini
Stéphanie
S
Robbiati
Valentina
V
Lasserre
Rémi
R
Gessain
Antoine
A
Gout
Olivier
O
Alcover
Andrés
A
Thoulouze
Maria-Isabel
MI
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
D015686:Gene Products, env; D003208:Concanavalin A