title: Cell-cell transmission allows human T-lymphotropic virus 1 to circumvent tetherin restriction.
abstract: Tetherin is part of the cellular innate immunity and impedes cell-free transmission of viruses that bud from the plasma membrane by retaining them on the cell surface. Some viruses have evolved activities in different proteins such as Vpu (HIV-1), K-protein (KSHV), Nef (SIV) or Env (HIV-2) to downregulate tetherin and overcome its restriction. We found that chronically HTLV-1 infected T-cell lines express eightfold more tetherin than uninfected transformed T-cell lines suggesting that tetherin expression is not inhibited by the virus. We observed that even small amounts of exogenous tetherin caused the retention of HTLV-1 on the cell surface and severely reduced cell-free infectivity of HTLV-1, but that cell-cell transmission, which is more relevant for HTLV-1, was significantly less decreased. However, knock-down of tetherin expresssion resulted in a slight increase in cell-cell infection indicating that the protein does not enhance this route of transmission.
authors.affiliation: HIV-Drug Resistance Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA. ilinskaa@mail.nih.gov
authors.forename: Anna
authors.initials: A
authors.lastname: Ilinskaya
authors.forename: David
authors.initials: D
authors.lastname: Derse
authors.forename: Shawn
authors.initials: S
authors.lastname: Hill
authors.forename: Gerald
authors.initials: G
authors.lastname: Princler
authors.forename: Gisela
authors.initials: G
authors.lastname: Heidecker
mesh_terms: D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000821:virology*; D002450:Cell Communication; D002460:Cell Line; D002461:Cell Line, Transformed; D058851:GPI-Linked Proteins / Q000235:genetics / Q000378:metabolism; D015368:Human T-lymphotropic virus 1 / Q000254:growth & development / Q000502:physiology*; D006801:Humans; D007113:Immunity, Innate; D034622:RNA Interference; D034741:RNA, Small Interfering; D013601:T-Lymphocytes / Q000276:immunology / Q000821:virology*; D057074:Virus Release; D000074010:Bone Marrow Stromal Antigen 2
chemical_list: D015703:Antigens, CD; D058851:GPI-Linked Proteins; D034741:RNA, Small Interfering; C094572:BST2 protein, human; D000074010:Bone Marrow Stromal Antigen 2