title: Human Adenovirus Type 37 Uses αVβ1and α3β1Integrins for Infection of Human Corneal Cells.
abstract: Epidemic keratoconjunctivitis (EKC) is a severe, contagious ocular disease that affects 20 to 40 million individuals worldwide every year. EKC is mainly caused by six types of human adenovirus (HAdV): HAdV-8, -19, -37, -53, -54, and -56. Of these, HAdV-8, -19, and -37 use sialic acid-containing glycans as cellular receptors. αVβ3, αVβ5, and a few additional integrins facilitate entry and endosomal release of other HAdVs. With the exception of a few biochemical analyses indicating that HAdV-37 can interact physically with αVβ5, little is known about the integrins used by EKC-causing HAdVs. Here, we investigated the overall integrin expression on human corneal cells and found expression of α2, α3, α6, αV, β1, and β4 subunits in human cornealin situepithelium and/or in a human corneal epithelial (HCE) cell line but no or less accessible expression of α4, α5, β3, or β5. We also identified the integrins used by HAdV-37 through a series of binding and infection competition experiments and different biochemical approaches. Together, our data suggest that HAdV-37 uses αVβ1 and α3β1 integrins for infection of human corneal epithelial cells. Furthermore, to confirm the relevance of these integrins in the HAdV-37 life cycle, we developed a corneal multilayer tissue system and found that HAdV-37 infection correlated well with the patterns of αV, α3, and β1 integrin expression. These results provide further insight into the tropism and pathogenesis of EKC-causing HAdVs and may be of importance for future development of new antiviral drugs.IMPORTANCEKeratitis is a hallmark of EKC, which is caused by six HAdV types (HAdV-8, -19, -37, -53, -54, and -56). HAdV-37 and some other HAdV types interact with integrin αVβ5 in order to enter nonocular human cells. In this study, we found that αVβ5 is not expressed on human corneal epithelial cells, thus proposing other host factors mediate corneal infection. Here, we first characterized integrin expression patterns on corneal tissue and corneal cells. Among the integrins identified, competition binding and infection experiments and biochemical assays pointed out αVβ1 and α3β1 to be of importance for HAdV-37 infection of corneal tissue. In the absence of a good animal model for EKC-causing HAdVs, we also developed anin vitrosystem with multilayer HCE cells and confirmed the relevance of the suggested integrins during HAdV-37 infection.
authors.affiliation: Division of Virology, Department of Clinical Microbiology, Umeå University, Umeå, Sweden.
authors.forename: Rickard J
authors.initials: RJ
authors.lastname: Storm
authors.affiliation: Division of Virology, Department of Clinical Microbiology, Umeå University, Umeå, Sweden.
authors.forename: B David
authors.initials: BD
authors.lastname: Persson
authors.affiliation: Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden.
authors.forename: Lars Nygård
authors.initials: LN
authors.lastname: Skalman
authors.affiliation: Division of Virology, Department of Clinical Microbiology, Umeå University, Umeå, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Frängsmyr
authors.affiliation: Department of Integrative Medical Biology, Umeå University, Umeå, Sweden.
authors.forename: Mona
authors.initials: M
authors.lastname: Lindström
authors.affiliation: Department of Public Health and Clinical Medicine, Norrland University Hospital (NUS), Umeå University, Umeå, Sweden.
authors.forename: Greg
authors.initials: G
authors.lastname: Rankin
authors.affiliation: Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden.|Department of Integrative Medical Biology, Umeå University, Umeå, Sweden.
authors.forename: Richard
authors.initials: R
authors.lastname: Lundmark
authors.affiliation: Department of Clinical Sciences, Ophthalmology, Umeå University, Umeå, Sweden.|Department of Integrative Medical Biology, Umeå University, Umeå, Sweden.
authors.forename: Fatima Pedrosa
authors.initials: FP
authors.lastname: Domellöf
authors.affiliation: Division of Virology, Department of Clinical Microbiology, Umeå University, Umeå, Sweden niklas.arnberg@umu.se.
authors.forename: Niklas
authors.initials: N
authors.lastname: Arnberg
mesh_terms: D000072283:A549 Cells; D000258:Adenovirus Infections, Human / Q000821:virology*; D000260:Adenoviruses, Human / Q000502:physiology*; D003315:Cornea / Q000473:pathology / Q000821:virology; D006801:Humans; D039201:Integrin alpha3beta1 / Q000502:physiology*; D011991:Receptors, Virus; D019030:Receptors, Vitronectin / Q000502:physiology*; D053585:Virus Attachment; D053586:Virus Internalization
chemical_list: D039201:Integrin alpha3beta1; D011991:Receptors, Virus; D019030:Receptors, Vitronectin; C094340:integrin alphavbeta1
keywords: adenoviruses; cornea; epidemic keratoconjunctivitis; integrins