title: Inverse relationship between pilus-mediated gonococcal adherence and surface expression of the pilus receptor, CD46.
abstract: Pilus-mediated adherence to mucosal epithelial cells is a critical step for Neisseria gonorrhoeae to establish an infection in the human host. CD46, the defined receptor for the gonococcal pilus, is a complement-regulatory protein that is expressed on all human nucleated cells. It was observed that a piliated, Opa(-) variant of gonococcal strain FA1090 adhered with different efficiencies to the human epithelial cell lines tested (Chang, ME180, HEC-1B and PC-3). Surprisingly, these differences in adherence levels did not correlate with levels of CD46 expressed by these cell lines. In fact, there was an inverse relationship between total surface-exposed CD46 and gonococcal adherence. Four major isoforms of CD46 are produced due to alternative RNA splicing of a surface-exposed region and the cytoplasmic tail. The relative isoform surface expression of each cell line was determined, and each was found to express different ratios of the four CD46 isoforms. No correlation could be derived between CD46 isoform surface expression and pilus-mediated gonococcal adherence, indicating that CD46 does not act as a classic receptor for gonococcal pili.
authors.affiliation: Department of Microbiology and Immunology, Northwestern University Medical School, 303 E. Chicago Ave, Searle 6-467, Chicago, IL 60611, USA1.
authors.forename: Deborah M
authors.initials: DM
authors.lastname: Tobiason
authors.affiliation: Department of Microbiology and Immunology, Northwestern University Medical School, 303 E. Chicago Ave, Searle 6-467, Chicago, IL 60611, USA1.
authors.forename: H Steven
authors.initials: HS
authors.lastname: Seifert
mesh_terms: D015703:Antigens, CD / Q000378:metabolism*; D001422:Bacterial Adhesion; D002460:Cell Line; D004847:Epithelial Cells / Q000382:microbiology; D010861:Fimbriae, Bacterial / Q000502:physiology*; D005434:Flow Cytometry; D006069:Gonorrhea / Q000382:microbiology; D006801:Humans; D051916:Membrane Cofactor Protein; D008562:Membrane Glycoproteins / Q000378:metabolism*; D009344:Neisseria gonorrhoeae / Q000472:pathogenicity* / Q000502:physiology
chemical_list: D015703:Antigens, CD; C497857:CD46 protein, human; D051916:Membrane Cofactor Protein; D008562:Membrane Glycoproteins