title: Canine adenovirus type 2 attachment and internalization: coxsackievirus-adenovirus receptor, alternative receptors, and an RGD-independent pathway.
abstract: The best-characterized receptors for adenoviruses (Ads) are the coxsackievirus-Ad receptor (CAR) and integrins alpha(v)beta(5) and alpha(v)beta(3), which facilitate entry. The alpha(v) integrins recognize an Arg-Gly-Asp (RGD) motif found in some extracellular matrix proteins and in the penton base in most human Ads. Using a canine adenovirus type 2 (CAV-2) vector, we found that CHO cells that express CAR but not wild-type CHO cells are susceptible to CAV-2 transduction. Cells expressing alpha(M)beta(2) integrins or major histocompatibility complex class I (MHC-I) molecules but which do not express CAR were not transduced. Binding assays showed that CAV-2 attaches to a recombinant soluble form of CAR and that Ad type 5 (Ad5) fiber, penton base, and an anti-CAR antibody partially blocked attachment. Using fluorescently labeled CAV-2 particles, we found that in some cells nonpermissive for transduction, inhibition was at the point of internalization and not attachment. The transduction efficiency of CAV-2, which lacks an RGD motif, surprisingly mimicked that of Ad5 when tested in cells selectively expressing alpha(v)beta(5) and alpha(v)beta(3) integrins. Our results demonstrate that CAV-2 transduction is augmented by CAR and possibly by alpha(v)beta(5), though transduction can be CAR and alpha(v)beta(3/5) independent but is alpha(M)beta(2), MHC-I, and RGD independent, demonstrating a transduction mechanism which is distinct from that of Ad2/5.
authors.affiliation: Généthon III and CNRS URA 1923, Evry, CNRS UMR 5537, Lyon, France.
authors.forename: C
authors.initials: C
authors.lastname: Soudais
authors.forename: S
authors.initials: S
authors.lastname: Boutin
authors.forename: S S
authors.initials: SS
authors.lastname: Hong
authors.forename: M
authors.initials: M
authors.lastname: Chillon
authors.forename: O
authors.initials: O
authors.lastname: Danos
authors.forename: J M
authors.initials: JM
authors.lastname: Bergelson
authors.forename: P
authors.initials: P
authors.lastname: Boulanger
authors.forename: E J
authors.initials: EJ
authors.lastname: Kremer
mesh_terms: D006516:Adenoviruses, Canine / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology*; D000818:Animals; D016466:CHO Cells; D002460:Cell Line; D062727:Coxsackie and Adenovirus Receptor-Like Membrane Protein; D006224:Cricetinae; D003713:Dendritic Cells / Q000378:metabolism; D004285:Dogs; D015395:Histocompatibility Antigens Class I / Q000378:metabolism; D006801:Humans; D016023:Integrins / Q000378:metabolism*; D011971:Receptors, Immunologic / Q000378:metabolism*; D018000:Receptors, Peptide / Q000378:metabolism*; D011991:Receptors, Virus / Q000378:metabolism*; D014161:Transduction, Genetic
chemical_list: C568771:CLMP protein, human; D062727:Coxsackie and Adenovirus Receptor-Like Membrane Protein; D015395:Histocompatibility Antigens Class I; D016023:Integrins; D011971:Receptors, Immunologic; D018000:Receptors, Peptide; D011991:Receptors, Virus; C051382:arginyl-glycyl-aspartic acid directed cell adhesion receptor