title: Total IgA and IgA reactivity to antigen I/II epitopes in HLA-DRB1*04 positive subjects.
abstract: Bacterial adherence to the acquired dental pellicle, important in dental caries (caries), is mediated by receptor-adhesins such as salivary agglutinin binding toStreptococcus mutansantigen I/II (I/II). Ten selected I/II epitopes were chosen to determine their reactivity to human salivary IgA. Previous studies suggested that a specific HLA biomarker group (HLA-DRB1*04) may have differential influence of immune responses to I/II. However, it was not known whether secretory IgA (SIgA) responses to the selected epitopes from HLA-DRB1*04 positive subjects were different compared to controls, or across other caries-related factors such as total IgA (TIgA). Thirty-two total subjects were matched according to HLA type, gender, ethnicity and age. HLA genotyping, oral bacterial, immunoglobulin and antibody analyses were performed. A large observed difference emerged with regard to the natural immune reservoir of TIgA in HLA-DRB1*04 positive subjects, specifically, a 27.6% reduction compared to controls. In contrast to all other epitopes studied, HLA-DRB1*04 positive subjects also exhibited reduced reactivity to I/II epitope 834-853. HLA-DRB1*04 positive subjects exhibited lower specific SIgA activity/TIgA to 834-853 and also a lower specific reactivity to 834-853/whole cellS. mutansUA159. Furthermore, HLA-DRB1*04 positive subjects exhibited lower responses to I/II in its entirety. The large observed difference in TIgA and the 834-853 reactivity pattern across multiple measures suggest potentially important connections pertaining to the link between HLA-DRB1*04 and caries.
authors.affiliation: Department of Pediatric Dentistry and Orthodontics, School of Dental Medicine, East Carolina University, Greenville, USA.
authors.forename: V Wallace
authors.initials: VW
authors.lastname: McCarlie
authors.affiliation: Center for Oral Health Research, Division of Orthodontics, Department of Oral Health Science, and Department of Microbiology, Immunology and Molecular Genetics, Colleges of Dentistry and Medicine, University of Kentucky, Lexington, USA.
authors.forename: James K
authors.initials: JK
authors.lastname: Hartsfield
authors.affiliation: Department of Microbiology and Immunology, School of Medicine, Indiana University, Indianapolis, USA.
authors.forename: Janice S
authors.initials: JS
authors.lastname: Blum
authors.affiliation: Department of Cariology, Restorative Sciences and Endodontics, School of Dentistry, University of Michigan, Ann Arbor, USA.
authors.forename: Carlos
authors.initials: C
authors.lastname: González-Cabezas
authors.affiliation: Department of Pediatric Dentistry, School of Dentistry, Indiana University, Indianapolis, USA.
authors.forename: Judith R
authors.initials: JR
authors.lastname: Chin
authors.affiliation: Department of Biostatistics, Schools of Medicine and Public Health, Indiana University, Indianapolis, USA.
authors.forename: George J
authors.initials: GJ
authors.lastname: Eckert
authors.affiliation: Center for Oral Health Research, Division of Orthodontics, Department of Oral Health Science, College of Dentistry, University of Kentucky, Lexington, USA.
authors.forename: Lorri A
authors.initials: LA
authors.lastname: Morford
authors.affiliation: Departments of Surgery and Microbiology and Immunology, School of Medicine, Indiana University, Indianapolis, USA.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Pescovitz
authors.affiliation: Department of Pediatrics, College of Medicine, University of South Florida, Tampa, USA.
authors.forename: Henry
authors.initials: H
authors.lastname: Rodriguez
authors.affiliation: Department of Cariology, Restorative Sciences and Endodontics, School of Dentistry, University of Michigan, Ann Arbor, USA.
authors.forename: Margherita
authors.initials: M
authors.lastname: Fontana
authors.affiliation: Departments of Oral Biology and Preventive and Community Dentistry, and Department of Pathology and Laboratory Medicine, Schools of Dentistry and Medicine, Indiana University, Indianapolis, USA.
authors.forename: Richard L
authors.initials: RL
authors.lastname: Gregory
keywords: DRB1; DRB1*04; Dental Caries; HLA-II; I/II; IgA; Immunogenetics; Immunomodulation; Streptococcus mutans