title: Attachment of Borrelia burgdorferi within Ixodes scapularis mediated by outer surface protein A.
abstract: Borrelia burgdorferi outer surface protein (Osp) A has been used as a Lyme disease vaccine that blocks transmission: OspA antibodies of immune hosts enter ticks during blood feeding and destroy spirochetes before transmission to the host can occur. B. burgdorferi produce OspA in the gut of unfed Ixodes scapularis ticks, and many spirochetes repress OspA production during the feeding process. This preferential expression suggests that OspA may have an important function in the vector. Here we show that OspA mediates spirochete attachment to the tick gut by binding to an I. scapularis protein. The binding domains reside in the central region and COOH-terminus of OspA. OspA also binds to itself, suggesting that spirochete-spirochete interactions may further facilitate adherence in the gut. OspA-mediated attachment in the tick provides a possible mechanism for how stage-specific protein expression can contribute to pathogenesis during the B. burgdorferi natural cycle.
authors.affiliation: Section of Rheumatology, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8031, USA.
authors.forename: U
authors.initials: U
authors.lastname: Pal
authors.forename: A M
authors.initials: AM
authors.lastname: de Silva
authors.forename: R R
authors.initials: RR
authors.lastname: Montgomery
authors.forename: D
authors.initials: D
authors.lastname: Fish
authors.forename: J
authors.initials: J
authors.lastname: Anguita
authors.forename: J F
authors.initials: JF
authors.lastname: Anderson
authors.forename: Y
authors.initials: Y
authors.lastname: Lobet
authors.forename: E
authors.initials: E
authors.lastname: Fikrig
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000954:Antigens, Surface / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D001096:Arachnid Vectors; D001422:Bacterial Adhesion / Q000235:genetics / Q000276:immunology / Q000502:physiology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D001428:Bacterial Vaccines; D001483:Base Sequence; D015748:Borrelia burgdorferi Group / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D004064:Digestive System / Q000382:microbiology; D006801:Humans; D018884:Ixodes / Q000382:microbiology*; D008074:Lipoproteins; D008193:Lyme Disease / Q000209:etiology / Q000517:prevention & control; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011485:Protein Binding
chemical_list: D000954:Antigens, Surface; D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines; D017931:DNA Primers; D008074:Lipoproteins; C072045:OspA protein