title: Actin- and clathrin-dependent mechanisms regulate interferon gamma release after stimulation of human immune cells with respiratory syncytial virus.
abstract: BACKGROUND
  Respiratory syncytial virus (RSV) can cause recurrent and severe respiratory tract infections. Cytoskeletal proteins are often involved during viral infections, either for cell entry or the initiation of the immune response. The importance of actin and clathrin dynamics for cell entry and the initiation of the cellular immune response against RSV in human immune cells is not known yet. The aim of this study was to investigate the role of actin and clathrin on cell entry of RSV and the subsequent effect on T cell activation and interferon gamma release in human immune cells.
  
  
  METHODS
  Peripheral blood mononuclear cells and purified monocytes were isolated from healthy adults and stimulated in vitro with RSV. Actin and clathrin dynamics were inhibited with respectively cytochalasin D and chlorpromazine. T cell receptor signaling was inhibited with cyclosporin A. Flow cytometry was used to determine the role of actin and clathrin on cell entry and T cell activation by RSV. Enzyme-linked immunosorbent assays were used to investigate the contribution of actin and clathrin on the release of interferon gamma.
  
  
  RESULTS
  Cell entry, virus gene transcription and interferon gamma release are actin-dependent. Post-endocytic processes like the increased expression of major histocompatibility complex II on monocytes , T cell activation and the release of interferon gamma are clathrin-dependent. Finally, T cell receptor signaling affects T cell activation, whereas soluble interleukin 18 is dispensable.
  
  
  CONCLUSIONS
  Analysis of cell entry and interferon gamma release after infection with RSV reveals the importance of actin- and clathrin-dependent signaling in human immune cells. Insights into the cellular biology of the human immune response against respiratory syncytial virus will provide a better understanding of disease pathogenesis and may prove useful in the development of preventive strategies.
authors.affiliation: Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud Institute for Molecular Life Science, Radboud university medical center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: Jop
authors.initials: J
authors.lastname: Jans
authors.affiliation: Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud Institute for Molecular Life Science, Radboud university medical center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: Hicham
authors.initials: H
authors.lastname: elMoussaoui
authors.affiliation: Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud Institute for Molecular Life Science, Radboud university medical center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: Ronald
authors.initials: R
authors.lastname: de Groot
authors.affiliation: Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud Institute for Molecular Life Science, Radboud university medical center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: Marien I
authors.initials: MI
authors.lastname: de Jonge
authors.affiliation: Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud Institute for Molecular Life Science, Radboud university medical center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands. gerben.ferwerda@radboudumc.nl.
authors.forename: Gerben
authors.initials: G
authors.lastname: Ferwerda
mesh_terms: D000199:Actins / Q000378:metabolism*; D000328:Adult; D002478:Cells, Cultured; D002966:Clathrin / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D054884:Host-Pathogen Interactions; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism*; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000821:virology; D012136:Respiratory Syncytial Viruses / Q000502:physiology*; D053586:Virus Internalization
chemical_list: D000199:Actins; D002966:Clathrin; D007371:Interferon-gamma
keywords: Cell entry; Innate immunity; Interferon gamma; Molecular biology; Monocytes; Respiratory syncytial virus; T cells