Human Parechovirus 1 Infection Occurs via αVβ1 Integrin

PLoS One. 2016 Apr 29;11(4):e0154769. doi: 10.1371/journal.pone.0154769. eCollection 2016.

Abstract

Human parechovirus 1 (HPeV-1) (family Picornaviridae) is a global cause of pediatric respiratory and CNS infections for which there is no treatment. Although biochemical and in vitro studies have suggested that HPeV-1 binds to αVβ1, αVβ3 and αVβ6 integrin receptor(s), the actual cellular receptors required for infectious entry of HPeV-1 remain unknown. In this paper we analyzed the expression profiles of αVβ1, αVβ3, αVβ6 and α5β1 in susceptible cell lines (A549, HeLa and SW480) to identify which integrin receptors support HPeV-1 internalization and/or replication cycle. We demonstrate by antibody blocking assay, immunofluorescence microscopy and RT-qPCR that HPeV-1 internalizes and replicates in cell lines that express αVβ1 integrin but not αVβ3 or αVβ6 integrins. To further study the role of β1 integrin, we used a mouse cell line, GE11-KO, which is deficient in β1 expression, and its derivate GE11-β1 in which human integrin β1 subunit is overexpressed. HPeV-1 (Harris strain) and three clinical HPeV-1 isolates did not internalize into GE11-KO whereas GE11-β1 supported the internalization process. An integrin β1-activating antibody, TS2/16, enhanced HPeV-1 infectivity, but infection occurred in the absence of visible receptor clustering. HPeV-1 also co-localized with β1 integrin on the cell surface, and HPeV-1 and β1 integrin co-endocytosed into the cells. In conclusion, our results demonstrate that in some cell lines the cellular entry of HPeV-1 is primarily mediated by the active form of αVβ1 integrin without visible receptor clustering.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Neoplasm / physiology
  • Cell Line
  • Cell Line, Tumor
  • HeLa Cells
  • Humans
  • Integrin alphaVbeta3 / physiology
  • Integrins / physiology
  • Mice
  • Parechovirus / pathogenicity*
  • Parechovirus / physiology
  • Picornaviridae Infections / etiology*
  • Picornaviridae Infections / physiopathology
  • Picornaviridae Infections / virology
  • Receptors, Virus / physiology
  • Receptors, Vitronectin / physiology*
  • Virus Internalization*

Substances

  • Antigens, Neoplasm
  • Integrin alphaVbeta3
  • Integrins
  • Receptors, Virus
  • Receptors, Vitronectin
  • integrin alphavbeta1
  • integrin alphavbeta6

Grants and funding

This work was supported by Turku Doctoral Programme of Molecular Medicine, The Finnish Cultural Foundation, European Union (AIROPico, FP7-PEOPLE-2013-IAPP Grant no. 612308)(http://airopico.eu), Academy of Finland (grant no. 128539 to P.S.)(www.aka.fi/en-GB/A/) and Jane and Aatos Erkko Foundation (to S.T.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.