title: HIV-1 immune activation induces Siglec-1 expression and enhances viral trans-infection in blood and tissue myeloid cells.
abstract: BACKGROUND
  Myeloid cells are key players in the recognition and response of the host against invading viruses. Paradoxically, upon HIV-1 infection, myeloid cells might also promote viral pathogenesis through trans-infection, a mechanism that promotes HIV-1 transmission to target cells via viral capture and storage. The receptor Siglec-1 (CD169) potently enhances HIV-1 trans-infection and is regulated by immune activating signals present throughout the course of HIV-1 infection, such as interferon α (IFNα).
  
  
  RESULTS
  Here we show that IFNα-activated dendritic cells, monocytes and macrophages have an enhanced ability to capture and trans-infect HIV-1 via Siglec-1 recognition of viral membrane gangliosides. Monocytes from untreated HIV-1-infected individuals trans-infect HIV-1 via Siglec-1, but this capacity diminishes after effective antiretroviral treatment. Furthermore, Siglec-1 is expressed on myeloid cells residing in lymphoid tissues, where it can mediate viral trans-infection.
  
  
  CONCLUSIONS
  Siglec-1 on myeloid cells could fuel novel CD4(+) T-cell infections and contribute to HIV-1 dissemination in vivo.
authors.affiliation: AIDS Research Institute IrsiCaixa, Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol IGTP, Universitat Autònoma de Barcelona, Badalona, Spain. mpino@irsicaixa.es.
authors.forename: Maria
authors.initials: M
authors.lastname: Pino
authors.affiliation: AIDS Research Institute IrsiCaixa, Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol IGTP, Universitat Autònoma de Barcelona, Badalona, Spain. ierkizia@irsicaixa.es.
authors.forename: Itziar
authors.initials: I
authors.lastname: Erkizia
authors.affiliation: AIDS Research Institute IrsiCaixa, Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol IGTP, Universitat Autònoma de Barcelona, Badalona, Spain. sbenet@irsicaixa.es.
authors.forename: Susana
authors.initials: S
authors.lastname: Benet
authors.affiliation: Institute of Medical Virology, National Reference Center for Retroviruses, University of Frankfurt, Frankfurt, Germany. Elina.Erikson@kgu.de.|Department of Infectious Diseases, Virology, Universitätsklinikum Heidelberg, Heidelberg, Germany. Elina.Erikson@kgu.de.
authors.forename: Elina
authors.initials: E
authors.lastname: Erikson
authors.affiliation: Pathology Department, University Hospital Germans Trias i Pujol (HUGTIP), Badalona, Spain. maiteffig@gmail.com.
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Fernández-Figueras
authors.affiliation: Otorhinolaryngology Department, HUGTIP, Badalona, Spain. lolagg1969@gmail.com.
authors.forename: Dolores
authors.initials: D
authors.lastname: Guerrero
authors.affiliation: AIDS Research Institute IrsiCaixa, Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol IGTP, Universitat Autònoma de Barcelona, Badalona, Spain. jdalmau@irsicaixa.es.
authors.forename: Judith
authors.initials: J
authors.lastname: Dalmau
authors.affiliation: AIDS Research Institute IrsiCaixa, Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol IGTP, Universitat Autònoma de Barcelona, Badalona, Spain. douchi@irsicaixa.es.
authors.forename: Dan
authors.initials: D
authors.lastname: Ouchi
authors.affiliation: Institute of Microbiology, University Hospital Center and University of Lausanne, Lausanne, Switzerland. rausell.biocomp@gmail.com.|Swiss Institute of Bioinformatics (SIB) - Vital-IT, Lausanne, Switzerland. rausell.biocomp@gmail.com.
authors.forename: Antonio
authors.initials: A
authors.lastname: Rausell
authors.affiliation: Institute of Microbiology, University Hospital Center and University of Lausanne, Lausanne, Switzerland. Angela.Ciuffi@chuv.ch.
authors.forename: Angela
authors.initials: A
authors.lastname: Ciuffi
authors.affiliation: Institute of Medical Virology, National Reference Center for Retroviruses, University of Frankfurt, Frankfurt, Germany. Oliver.Keppler@kgu.de.
authors.forename: Oliver T
authors.initials: OT
authors.lastname: Keppler
authors.affiliation: Institute of Microbiology, University Hospital Center and University of Lausanne, Lausanne, Switzerland. atelenti@jcvi.org.|Current address: The J. Craig Venter Institute, La Jolla, CA, USA. atelenti@jcvi.org.
authors.forename: Amalio
authors.initials: A
authors.lastname: Telenti
authors.affiliation: Department of Infectious Diseases, Virology, Universitätsklinikum Heidelberg, Heidelberg, Germany. hans-georg.kraeusslich@med.uni-heidelberg.de.
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Kräusslich
authors.affiliation: AIDS Research Institute IrsiCaixa, Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol IGTP, Universitat Autònoma de Barcelona, Badalona, Spain. jmpicado@irsicaixa.es.|Institució Catalana de Recerca i Estudis Avançats ICREA, Barcelona, Spain. jmpicado@irsicaixa.es.|University of Vic-Central University of Catalonia (UVic-UCC), Vic, Spain. jmpicado@irsicaixa.es.
authors.forename: Javier
authors.initials: J
authors.lastname: Martinez-Picado
authors.affiliation: AIDS Research Institute IrsiCaixa, Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol IGTP, Universitat Autònoma de Barcelona, Badalona, Spain. nizquierdo@irsicaixa.es.
authors.forename: Nuria
authors.initials: N
authors.lastname: Izquierdo-Useros
mesh_terms: D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000821:virology; D002478:Cells, Cultured; D015497:HIV-1 / Q000276:immunology* / Q000502:physiology*; D006801:Humans; D016898:Interferon-alpha / Q000378:metabolism*; D008297:Male; D022423:Myeloid Cells / Q000821:virology*; D063267:Sialic Acid Binding Ig-like Lectin 1 / Q000096:biosynthesis*; D015854:Up-Regulation
chemical_list: D016898:Interferon-alpha; D063267:Sialic Acid Binding Ig-like Lectin 1