title: Antibody response to the 45 kDa Candida albicans antigen in an animal model and potential role of the antigen in adherence.
abstract: The Candida antigen CR3-RP (complement receptor 3-related protein) is supposed to be a 'mimicry' protein because of its ability to bind antibody directed against the alpha subunit of the mammalian CR3 (CD11b/CD18). This study aimed to (i) investigate the specific humoral isotypic response to immunization with CR3-RP in vivo in a rabbit animal model, and (ii) determine the role of CR3-RP in the adherence of Candida albicans in vitro using the model systems of buccal epithelial cells (BECs) and biofilm formation. The synthetic C. albicans peptide DINGGGATLPQ corresponding to 11 amino-acids of the CR3-RP sequence DINGGGATLPQALXQITGVIT, determined by N-terminal sequencing, was used for immunization of rabbits to obtain polyclonal anti-CR3-PR serum and for subsequent characterization of the humoral isotypic response of rabbits. A significant increase of IgG, IgA and IgM anti-CR3-RP specific antibodies was observed after the third (P<0.01) and the fourth (P<0.001) immunization doses. The elevation of IgA levels suggested peptide immunomodulation of the IgA1 subclass, presumably in coincidence with Candida epithelial adherence. Blocking CR3-RP with polyclonal anti-CR3-RP serum reduced the ability of Candida to adhere to BECs, in comparison with the control, by up to 35 % (P<0.001), and reduced biofilm formation by 28 % (P<0.001), including changes in biofilm thickness and integrity detected by confocal laser scanning microscopy. These properties of CR3-RP suggest that it has potential for future vaccine development.
authors.affiliation: Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia.
authors.forename: Helena
authors.initials: H
authors.lastname: Bujdáková
authors.affiliation: Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia.
authors.forename: Ema
authors.initials: E
authors.lastname: Paulovičová
authors.affiliation: Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia.
authors.forename: Silvia
authors.initials: S
authors.lastname: Borecká-Melkusová
authors.affiliation: Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia.
authors.forename: Juraj
authors.initials: J
authors.lastname: Gašperík
authors.affiliation: Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia.
authors.forename: Soňa
authors.initials: S
authors.lastname: Kucharíková
authors.affiliation: Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia.
authors.forename: Anna
authors.initials: A
authors.lastname: Kolecka
authors.affiliation: Department of Hygiene, Microbiology and Social Medicine, Innsbruck Medical University, Austria.
authors.forename: Claudia
authors.initials: C
authors.lastname: Lell
authors.affiliation: Department of Hygiene, Microbiology and Social Medicine, Innsbruck Medical University, Austria.
authors.forename: Dorthe B
authors.initials: DB
authors.lastname: Jensen
authors.affiliation: Department of Hygiene, Microbiology and Social Medicine, Innsbruck Medical University, Austria.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Würzner
authors.affiliation: Department of Biophotonics, International Laser Centre, Bratislava, Slovakia.
authors.forename: Dušan
authors.initials: D
authors.lastname: Chorvát
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
authors.forename: Iva
authors.initials: I
authors.lastname: Pichová
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000908:Antibodies, Fungal / Q000097:blood*; D000946:Antigens, Fungal / Q000008:administration & dosage / Q000737:chemistry / Q000276:immunology*; D018441:Biofilms / Q000254:growth & development; D002176:Candida albicans / Q000254:growth & development / Q000276:immunology* / Q000472:pathogenicity* / Q000502:physiology; D002448:Cell Adhesion; D004195:Disease Models, Animal; D004847:Epithelial Cells / Q000382:microbiology; D005656:Fungal Proteins / Q000008:administration & dosage / Q000737:chemistry / Q000276:immunology; D006801:Humans; D007114:Immunization; D008969:Molecular Sequence Data; D009061:Mouth Mucosa / Q000166:cytology / Q000382:microbiology; D011817:Rabbits; D011951:Receptors, Complement / Q000008:administration & dosage / Q000737:chemistry / Q000276:immunology
chemical_list: D000908:Antibodies, Fungal; D000946:Antigens, Fungal; D005656:Fungal Proteins; D011951:Receptors, Complement