Abstract
Many pathogenic bacteria possess cell surface receptors which can bind immunoglobulins via the Fc portion. The aim of this study was to characterize the human immunoglobulin G (IgG) Fc-binding activity of Prevotella intermedia, a suspected etiologic agent of adult chronic periodontitis. The Fc-binding activity of P. intermedia on whole cells and on extracellular vesicles was demonstrated. Incubation of P. intermedia cells in the presence of Zwittergent 3-14 allowed complete solubilization of the Fc receptor from the cell surface. This cell envelope extract was thus used to characterize the Fc-binding activity. A microtiter plate assay using alkaline phosphatase-labeled Fc fragments showed that preincubation of the cell envelope extract with human IgG, human IgG Fc fragments, or human serum completely inhibited the Fc-binding activity. Partial inhibition was obtained with human IgG F(ab')2 fragments, whereas no inhibition occurred following preincubation with human IgA, carbohydrates, and selected proteins. Preincubation of the cell envelope extract with IgG from a variety of animals demonstrated that rabbit, mouse, rat, goat, and sheep IgG did not inhibit Fc-binding activity, whereas cow, pig, and dog IgG partially inhibited Fc-binding activity. A strong inhibition comparable to that obtained with human IgG was noted with monkey IgG. The Fc receptor of P. intermedia is thus different from the six types previously reported in other nonoral bacteria. Polyacrylamide gel electrophoresis and Western blotting (immunoblotting) analysis of the cell envelope extract revealed a major band with a molecular mass of approximately 65 kDa which reacted with peroxidase-labeled human IgG Fe fragments. Transmission electron microscopy showed a uniform distribution of the Fc receptor on the bacterial surface, as revealed by gold labeling. The Fc-binding activity demonstrated in this study may act as an additional virulence factor for P. intermedia by reducing IgG reactions with the bacterial cell.
Full Text
The Full Text of this article is available as a PDF (329.8 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Dahlén G. G. Black-pigmented gram-negative anaerobes in periodontitis. FEMS Immunol Med Microbiol. 1993 Mar;6(2-3):181–192. doi: 10.1111/j.1574-695X.1993.tb00323.x. [DOI] [PubMed] [Google Scholar]
- Forsgren A., Sjöquist J. "Protein A" from S. aureus. I. Pseudo-immune reaction with human gamma-globulin. J Immunol. 1966 Dec;97(6):822–827. [PubMed] [Google Scholar]
- Goward C. R., Scawen M. D., Murphy J. P., Atkinson T. Molecular evolution of bacterial cell-surface proteins. Trends Biochem Sci. 1993 Apr;18(4):136–140. doi: 10.1016/0968-0004(93)90021-e. [DOI] [PubMed] [Google Scholar]
- Grenier D., Labbé S., Mouton C., Meyrand D. Hydrolytic enzymes and lectin-binding activity of black-pigmented anaerobic rods. Microbiology. 1994 Apr;140(Pt 4):873–878. doi: 10.1099/00221287-140-4-873. [DOI] [PubMed] [Google Scholar]
- Grenier D., Michaud J. Demonstration of human immunoglobulin G Fc-binding activity in oral bacteria. Clin Diagn Lab Immunol. 1994 Mar;1(2):247–249. doi: 10.1128/cdli.1.2.247-249.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kalfas S., Tigyi Z., Wikström M., Naidu A. S. Laminin binding to Prevotella intermedia. Oral Microbiol Immunol. 1992 Aug;7(4):235–239. doi: 10.1111/j.1399-302x.1992.tb00031.x. [DOI] [PubMed] [Google Scholar]
- LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
- Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
- Lantz M. S., Switalski L. M., Kornman K. S., Hök M. Bacteroides intermedius binds fibrinogen. J Bacteriol. 1985 Aug;163(2):623–628. doi: 10.1128/jb.163.2.623-628.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mintz K. P., Fives-Taylor P. M. Identification of an immunoglobulin Fc receptor of Actinobacillus actinomycetemcomitans. Infect Immun. 1994 Oct;62(10):4500–4505. doi: 10.1128/iai.62.10.4500-4505.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nesbitt W. E., Fukushima H., Leung K. P., Clark W. B. Coaggregation of Prevotella intermedia with oral Actinomyces species. Infect Immun. 1993 May;61(5):2011–2014. doi: 10.1128/iai.61.5.2011-2014.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Raeder R., Boyle M. D. Association between expression of immunoglobulin G-binding proteins by group A streptococci and virulence in a mouse skin infection model. Infect Immun. 1993 Apr;61(4):1378–1384. doi: 10.1128/iai.61.4.1378-1384.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Reis K. J., Ayoub E. M., Boyle M. D. Streptococcal Fc receptors. I. Isolation and partial characterization of the receptor from a group C streptococcus. J Immunol. 1984 Jun;132(6):3091–3097. [PubMed] [Google Scholar]
- Slots J., Listgarten M. A. Bacteroides gingivalis, Bacteroides intermedius and Actinobacillus actinomycetemcomitans in human periodontal diseases. J Clin Periodontol. 1988 Feb;15(2):85–93. doi: 10.1111/j.1600-051x.1988.tb00999.x. [DOI] [PubMed] [Google Scholar]
- Sundqvist G., Carlsson J., Herrmann B., Tärnvik A. Degradation of human immunoglobulins G and M and complement factors C3 and C5 by black-pigmented Bacteroides. J Med Microbiol. 1985 Feb;19(1):85–94. doi: 10.1099/00222615-19-1-85. [DOI] [PubMed] [Google Scholar]
- Tolo K., Helgeland K. Fc-binding components: a virulence factor in Actinobacillus actinomycetemcomitans? Oral Microbiol Immunol. 1991 Dec;6(6):373–377. doi: 10.1111/j.1399-302x.1991.tb00509.x. [DOI] [PubMed] [Google Scholar]
- Widders P. R., Dorrance L. A., Yarnall M., Corbeil L. B. Immunoglobulin-binding activity among pathogenic and carrier isolates of Haemophilus somnus. Infect Immun. 1989 Feb;57(2):639–642. doi: 10.1128/iai.57.2.639-642.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]