title: Membrane cofactor protein is a receptor for adenoviruses associated with epidemic keratoconjunctivitis.
abstract: Subgroup D adenovirus (Ad) types 8, 19, and 37 (Ad8, -19, and -37, respectively) are causative agents of epidemic keratoconjunctivitis and genital tract infections. Previous studies showed that Ad37 binds to a 50-kDa membrane glycoprotein expressed on human ocular (conjunctival) cells. To identify and characterize the role of the 50-kDa glycoprotein in Ad37 infection, we partially purified this molecule from solubilized Chang C conjunctival cell membranes by using lentil lectin chromatography and preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Liquid chromatography coupled to nano-electrospray ionization-tandem mass spectrometry was subsequently used to identify four Ad37 receptor candidates: CD46, CD87, CD98, and CD147. Immunodepletion analyses demonstrated that the 50-kDa protein is identical to CD46 (also known as membrane cofactor protein). The Ad37, but not Ad5, fiber knob bound to the extracellular domain of CD46, demonstrating a direct interaction of an Ad37 capsid protein with CD46. An antibody specific for the N-terminal 19 amino acids of CD46 also blocked Ad37 infection of human cervical carcinoma and conjunctival cells, indicating a requirement for CD46 in infection. Finally, expression of a 50-kDa isoform of human CD46 in a CD46-null cell line increased cell binding by wild-type Ad37 and gene delivery by an Ad vector pseudotyped with the Ad37 fiber, but not by a vector bearing the Ad5 fiber. Together, these studies demonstrate that CD46 serves as an attachment receptor for Ad37 and shed further light on the cell entry pathway of subgroup D Ads.
authors.affiliation: Department of Immunology, The Scripps Research Institute, La Jolla, California 92037, USA.
authors.forename: Eugene
authors.initials: E
authors.lastname: Wu
authors.forename: Sunia A
authors.initials: SA
authors.lastname: Trauger
authors.forename: Lars
authors.initials: L
authors.lastname: Pache
authors.forename: Tina-Marie
authors.initials: TM
authors.lastname: Mullen
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: von Seggern
authors.forename: Gary
authors.initials: G
authors.lastname: Siuzdak
authors.forename: Glen R
authors.initials: GR
authors.lastname: Nemerow
mesh_terms: D000257:Adenoviridae Infections / Q000209:etiology* / Q000821:virology; D000260:Adenoviruses, Human / Q000145:classification / Q000235:genetics / Q000472:pathogenicity*; D000595:Amino Acid Sequence; D000818:Animals; D015703:Antigens, CD / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D001483:Base Sequence; D016466:CHO Cells; D002460:Cell Line; D006224:Cricetinae; D004279:DNA, Viral / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D007637:Keratoconjunctivitis / Q000209:etiology* / Q000821:virology; D051916:Membrane Cofactor Protein; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D008969:Molecular Sequence Data; D011991:Receptors, Virus / Q000737:chemistry / Q000235:genetics / Q000502:physiology*
chemical_list: D015703:Antigens, CD; C497857:CD46 protein, human; D004279:DNA, Viral; D051916:Membrane Cofactor Protein; D008562:Membrane Glycoproteins; D011991:Receptors, Virus