Aspiration pneumonia is a life-threatening infectious disease often caused by oral anaerobic and periodontal pathogens such as Porphyromonas gingivalis. This organism produces proteolytic enzymes, known as gingipains, which manipulate innate immune responses and promote chronic inflammation. Here, we challenged mice with P. gingivalis W83 and examined the role of gingipains in bronchopneumonia, lung abscess formation, and inflammatory responses. Although gingipains were not required for P. gingivalis colonization and survival in the lungs, they were essential for manifestation of clinical symptoms and infection-related mortality. Pathologies caused by wild-type (WT) P. gingivalis W83, including hemorrhage, necrosis, and neutrophil infiltration, were absent from lungs infected with gingipain-null isogenic strains or WT bacteria preincubated with gingipain-specific inhibitors. Damage to lung tissue correlated with systemic inflammatory responses, as manifested by elevated levels of TNF, IL-6, IL-17, and C-reactive protein. These effects were unequivocally dependent on gingipain activity. Gingipain activity was also implicated in the observed increase in IL-17 in lung tissues. Furthermore, gingipains increased platelet counts in the blood and activated platelets in the lungs. Arginine-specific gingipains made a greater contribution to P. gingivalis- related morbidity and mortality than lysine-specific gingipains. Thus, inhibition of gingipain may be a useful adjunct treatment for P. gingivalis- mediated aspiration pneumonia.

Keywords:
Aspiration pneumonia, Porphyromonas gingivalis, Gingipain
1.
Terpenning MS, Taylor GW, Lopatin DE, Kerr CK, Dominguez BL, et al: Aspiration pneumonia: dental and oral risk factors in an older veteran population. J Am Geriatr Soc 2001;49:557-563.
2.
De Pablo P, Chapple ILC, Buckley CD, Dietrich T: Periodontitis in systemic rheumatic diseases. Nat Rev Rheumatol 2009;5:218-224.
3.
Friedewald VE, Kornman KS, Beck JD, Genco R, Goldfine A, et al: The American Journal of Cardiology and Journal of Periodontology Editors' Consensus: periodontitis and atherosclerotic cardiovascular disease. Am J Cardiol 2009;104:59-68.
4.
Chambrone L, Guglielmetti MR, Pannuti CM, Chambrone LA: Evidence grade associating periodontitis to preterm birth and/or low birth weight. 1. A systematic review of prospective cohort studies. J Clin Periodontol 2011;38:795-808.
5.
Bartlett JG: How important are anaerobic bacteria in aspiration pneumonia: when should they be treated and what is optimal therapy. Infect Dis Clin North Am 2013;27:149-155.
6.
Bansal M, Khatri M, Taneja V: Potential role of periodontal infection in respiratory diseases - a review. J Med Life 2013;15:244-248.
7.
Scannapieco FA, Shay K: Oral health disparities in older adults: oral bacteria, inflammation, and aspiration pneumonia. Dent Clin North Am 2014;58:771-782.
8.
Albandar JM, Rams TE: Global epidemiology of periodontal diseases: an overview. Periodontol 2000;29:7-10.
9.
Cobb CM, Williams KB, Gerkovitch MM: Is the prevalence of periodontitis in the USA in decline? Periodontol 2000;50:13-24.
10.
Bartlett JG, Gorbach SL, Finegold SM: The bacteriology of aspiration pneumonia. Am J Med 1974;56:202-207.
11.
Finegold SM, Strong CA, McTeague M, Marina M: The importance of black-pigmented Gram-negative anaerobes in human infections. FEMS Immunol Med Microbiol 1993;6:77-82.
12.
Zijlstra EE, Swart GR, Godfroy FJ, Degener JE: Pericarditis, pneumonia and brain abscess due to a combined Actinomyces-Actinobacillus actinomycetemcomitans infection. J Infect 1992;25:83-87.
13.
Morris JF, Sewell DL: Necrotizing pneumonia caused by mixed infection with Actinobacillus actinomycetemcomitans and Actinomyces israelii: case report and review. Clin Infect Dis 1994;18:450-452.
14.
Scannapieco FA: Role of oral bacteria in respiratory infection. J Periodontol 1999;70:793-802.
15.
Okuda K, Kimizuka R, Abe S, Kato T, Ishihara K: Involvement of periodontopathic anaerobes in aspiration pneumonia. J Periodontol 2005;76:2154-2160.
16.
Ashimoto A, Chen C, Bakker I, Slots J: Polymerase chain reaction detection of 8 putative periodontal pathogens in subgingival plaque of gingivitis and advanced periodontitis lesions. Oral Microbiol Immunol 1996;11:266-273.
17.
Lamont RJ, Jenkinson HF: Life below the gum line: pathogenic mechanisms of Porphyromonas gingivalis. Microbiol Mol Biol Rev 1998;62:1244-1263.
18.
Socransky SS, Haffajee AD, Cugini MA, Smith C, Kent RL: Microbial complexes in subgingival plaque. J Clin Periodontol 1998;25:134-144.
19.
Holt SC, Ebersole JL: Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia: the ‘red complex', a prototype polybacterial pathogenic consortium in periodontitis. Periodontol 2000;38:72-122.
20.
Darveau RP: The oral microbial consortium's interaction with the periodontal innate defense system. DNA Cell Biol 2009;28:389-395.
21.
Hajishengallis G: Porphyromonas gingivalis-host interactions: open war or intelligent guerilla tactics? Microbes Infect 2009;11:637-645.
22.
Kadowaki T, Takii R, Yamatake K, Kawakubo T, Tsukuba T, et al: A role for gingipains in cellular responses and bacterial survival in Porphyromonas gingivalis- infected cells. Front Biosci 2007;12:4800-4809.
23.
Guo Y, Nguyen K-A, Potempa J: Dichotomy of gingipains action as virulence factors: from cleaving substrates with the precision of a surgeon's knife to a meat chopper-like brutal degradation of proteins. Periodontol 2000 2010;54:15-44.
24.
Bostanci N, Belibasakis GN: Porphyromonas gingivalis: an invasive and evasive opportunistic oral pathogen. FEMS Microbiol Lett 2012;333:1-9.
25.
Potempa J, Pavloff N, Travis J: Porphyromonas gingivalis: a proteinase/gene accounting audit. Trends Microbiol 1995;3:430-434.
26.
Li N, Collyer CA: Gingipains from Porphyromonas gingivalis - complex domain structures confer diverse functions. Eur J Microbiol Immunol 2011;1:41-58.
27.
Potempa J, Sroka A, Imamura T, Travis J: Gingipains, the major cysteine proteinases and virulence factors of Porphyromonas gingivalis: structure, function and assembly of multidomain protein complexes. Curr Protein Pept Sci 2003;4:397-407.
28.
Laugisch O, Schacht M, Guentsch A, Kantyka T, Sroka A, et al: Periodontal pathogens affect the level of protease inhibitors in gingival crevicular fluid. Mol Oral Microbiol 2012;27:45-56.
29.
Popadiak K, Potempa J, Riesbeck K, Blom AM: Biphasic effect of gingipains from Porphyromonas gingivalis on the human complement system. J Immunol 2007;178:7242-7250.
30.
Potempa M, Potempa J: Protease-dependent mechanisms of complement evasion by bacterial pathogens. Biol Chem 2012;393:873-888.
31.
Kadowaki T, Baba A, Abe N, Takii R, Hashimoto M, et al: Suppression of pathogenicity of Porphyromonas gingivalis by newly developed gingipain inhibitors. Mol Pharmacol 2004;66:1599-1606.
32.
Baba A, Kadowaki T, Asao T, Yamamoto K: Roles for Arg- and Lys-gingipains in the disruption of cytokine responses and loss of viability of human endothelial cells by Porphyromonas gingivalis infection. Biol Chem 2002;383:1223-1230.
33.
Bodet C, Chandad F, Grenier D: Modulation of cytokine production by Porphyromonas gingivalis in a macrophage and epithelial cell co-culture model. Microbes Infect 2005;7:448-456.
34.
Mezyk-Kopec R, Bzowska M, Potempa J, Bzowska M, Jura N, et al: Inactivation of membrane tumor necrosis factor alpha by gingipains from Porphyromonas gingivalis. Infect Immun 2005;73:1506-1514.
35.
Yun PLW, Decarlo AA, Chapple CC, Collyer CA, Hunter N: Binding of Porphyromonas gingivalis gingipains to human CD4(+) T cells preferentially down-regulates surface CD2 and CD4 with little affect on co-stimulatory molecule expression. Microb Pathog 2005;38:85-96.
36.
Yun LWP, Decarlo AA, Hunter N: Blockade of protease-activated receptors on T cells correlates with altered proteolysis of CD27 by gingipains of Porphyromonas gingivalis. Clin Exp Immunol 2007;150:217-229.
37.
Hajishengallis G, Wang M, Bagby GJ, Nelson S: Importance of TLR2 in early innate immune response to acute pulmonary infection with Porphyromonas gingivalis in mice. J Immunol 2008;181:4141-4149.
38.
Nelson S, Laughon BE, Summer WR, Eckhaus MA, Bartlett JG, et al: Characterization of the pulmonary inflammatory response to an anaerobic bacterial challenge. Am Rev Respir Dis 1986;133:212-217.
39.
Nemec A, Pavlica Z, Nemec-Svete A, Eržen D, Milutinović A, et al: Aerosolized clindamycin is superior to aerosolized dexamethasone or clindamycin-dexamethasone combination in the treatment of severe Porphyromonas gingivalis aspiration pneumonia in an experimental murine model. Exp Lung Res 2012;38:9-18.
40.
Pace CC, McCullough GH: The association between oral microorgansims and aspiration pneumonia in the institutionalized elderly: review and recommendations. Dysphagia 2010;25:307-322.
41.
Terpenning MS, Taylor GW, Lopatin DE, Kerr CK, Dominguez BL, Loesche WJ: Aspiration pneumonia: dental and oral risk factors in an older veteran population. J Am Geriatr Soc 2001;49:557-563.
42.
Kadowaki T, Baba A, Abe N, Takii R, Hashimoto M, et al: Suppression of pathogenicity of Porphyromonas gingivalis by newly developed gingipain inhibitors. Mol Pharmacol 2004;66:1599-1606.
43.
Kimizuka R, Kato T, Ishihara K, Okuda K: Mixed infections with Porphyromonas gingivalis and Treponema denticola cause excessive inflammatory responses in a mouse pneumonia model compared with monoinfections. Microbes Infect 2003;5:1357-1362.
44.
Petelin M, Naruishi K, Shiomi N, Mineshiba J, Arai H, et al: Systemic up-regulation of sTNFR2 and IL-6 in Porphyromonas gingivalis pneumonia in mice. Exp Mol Pathol 2004;76:76-81.
45.
Message SD, Johnston SL: Host defense function of the airway epithelium in health and disease: clinical background. J Leukoc Biol 2004;75:5-17.
46.
Mobarrez F, Sjövik C, Soop A, Hållström L, Frostell C, et al: CD40L expression in plasma of volunteers following LPS administration: a comparison between assay of CD40L on plateletmicrovesicles and soluble CD40L. Platelets 2014;25:1-5.
47.
Nurden AT: Platelets, inflammation and tissue regeneration. Thromb Haemost 2011;105(suppl 1):S13-S33.
48.
McGovern Murphy F, Raymond M, Menard PA, Bejar-Ardiles KR, Carignan A, Lesur O: Ventilator associated pneumonia and endotracheal tube repositioning: an underrated risk factor. Am J Infect Control 2014;42:1328-1330.
49.
Schallom M, Dykeman B, Metheny N, Kirby J, Pierce J: Head-of-bed elevation and early outcomes of gastric reflux, aspiration and pressure ulcers: a feasibility study. Am J Crit Care 2015;24:57-66.
50.
Kesavalu L, Holt SC, Ebersole JL: Trypsin-like protease activity of Porphyromonas gingivalis as a potential virulence factor in a murine lesion model. Microb Pathog 1996;20:1-10.
51.
Genco CA, Odusanya BM, Potempa J, Mikolajczyk-Pawlinska J, Travis J: A peptide domain on gingipain R which confers immunity against Porphyromonas gingivalis infection in mice. Infect Immun 1998;66:4108-4114.
52.
Montecino-Rodriguez E, Berent-Maoz B, Dorshkind K: Causes, consequences, and reversal of immune system aging. J Clin Invest 2013;123:958-965.
53.
van der Maarel-Wierink CD, Vanobbergen JN, Bronkhorst EM, Schols JM, de Baat C: Risk factors for aspiration pneumonia in frail older people: a systematic literature review. J Am Med Dir Assoc 2011;12:344-354.
54.
Discipio RG, Daffern PJ, Kawahara M, Pike R, Travis J, et al: Cleavage of human complement component C5 by cysteine proteinases from Porphyromonas (Bacteroides) gingivalis: prior oxidation of C5 augments proteinase digestion of C5. Immunology 1996;87:660-667.
55.
Rapala-Kozik M, Bras G, Chruscicka B, Karkowska-Kuleta J, Sroka A, et al: Adsorption of components of the plasma kinin-forming system on the surface of Porphyromonas gingivalis involves gingipains as the major docking platforms. Infect Immun 2011;79:797-805.
56.
Imamura T, Pike RN, Potempa J, Travis J: Pathogenesis of periodontitis: a major arginine-specific cysteine proteinase from Porphyromonas gingivalis induces vascular permeability enhancement through activation of the kallikrein/kinin pathway. J Clin Invest 1994;94:361-367.
57.
Imamura T, Potempa J, Tanase S, Travis J: Activation of blood coagulation factor X by arginine-specific cysteine proteinases (gingipain-Rs) from Porphyromonas gingivalis. J Biol Chem 1997;272:16062-16067.
58.
Imamura T, Tanase S, Hamamoto T, Potempa J, Travis J: Activation of blood coagulation factor IX by gingipains R, arginine-specific cysteine proteinases from Porphyromonas gingivalis. Biochem J 2001;353:325-331.
59.
Imamura T, Banbula A, Pereira PJ, Travis J, Potempa J: Activation of human prothrombin by arginine-specific cysteine proteinases (gingipains R) from Porphyromonas gingivalis. J Biol Chem 2001;276:18984-18991.
60.
Imamura T, Potempa J, Pike RN, Moore JN, Barton MH, Travis J: Effect of free and vesicle-bound cysteine proteinases of Porphyromonas gingivalis on plasma clot formation: implications for bleeding tendency at periodontitis sites. Infect Immun 1995;63:4877-4782.
61.
Lourbakos A, Yuan YP, Jenkins AL, Travis J, Andrade-Gordon P, et al: Activation of protease-activated receptors by gingipains from Porphyromonas gingivalis leads to platelet aggregation: a new trait in microbiology pathogenicity. Blood 2001;97:3790-3797.
62.
Lourbakos A, Chinni C, Thompson P, Potempa J, Travis J, et al: Cleavage and activation of proteinase-activated receptor-2 on human neutrophils by gingipain-R from Porphyromonas gingivalis. FEBS Lett 1998;435:45-48.
63.
Lourbakos A, Potempa J, Travis J, D'Andrea MR, Andrade-Gordon P, et al: Arginine-specific protease from Porphyromonas gingivalis activates protease-activated receptors on human oral epithelial cells and induces interleukin-6 secretion. Infect Immun 2001;69:5121-5130.
64.
Uehara A, Muramoto K, Imamura T, Nakayama K, Potempa J, Travis J, et al: Arginine-specific gingipains from Porphyromonas gingivalis stimulate production of hepatocyte growth factor (scatter factor) through protease-activated receptors in human gingival fibroblasts in culture. J Immunol 2005;175:6076-6084.
65.
Monteiro AC, Scovino A, Raposo S, Gaze VM, Cruz C, Svensjö E, et al: Kinin danger signals proteolytically released by gingipain induce fimbriae-specific IFN-gamma- and IL-17-producing T cells in mice infected intramucosally with Porphyromonas gingivalis. J Immunol 2009;183:3700-3711.
66.
Marwaha N: Thrombocytosis as a predictor of serious bacterial infection. Indian Pediatr 2010;47:923-924.
67.
Nagahisa H, Nagata Y, Ohnuki T, Osada M, Nagasawa T, Abe T, et al: Bone marrow stromal cells produce thrombopoietin and stimulate megakaryocyte growth and maturation but suppress proplatelet formation. Blood 1996;87:1309-1316.
68.
McNicol A, Israels SJ: Mechanisms of oral bacteria-induced platelet activation. Can J Physiol Pharmacol 2010;88:510-524.
69.
Gleissner CA, von Hundelshausen P, Ley K: Platelet chemokines in vascular disease. Arterioscler Thromb Vasc Biol 2008;28:1920-1927.
70.
Naito M, Sakai E, Shi Y, Ideguchi H, Shoji M, et al: Porphyromonas gingivalis- induced platelet aggregation in plasma depends on Hgp44 adhesin but not Rgp proteinase. Mol Microbiol 2006;59:152-167.
71.
Tang YQ, Yeaman MR, Selsted ME: Antimicrobial peptides from human platelets. Infect Immun 2002;70:6524-65633.
72.
Katz J, Sambandam V, Wu JH, Michalek SM, Balkovetz DF: Characterization of Porphyromonas gingivalis- induced degradation of epithelial cell junctional complexes. Infect Immun 2000;68:1441-1449.
73.
Imamura T, Potempa J, Pike RN, Travis J: Dependence of vascular permeability enhancement on cysteine proteinases in vesicles of Porphyromonas gingivalis. Infect Immun 1995;63:1999-2003.
74.
Scott CF, Whitaker EJ, Hammond BF, Colman RW: Purification and characterization of a potent 70-kDa thiol lysyl-proteinase (Lys-gingivain) from Porphyromonas gingivalis that cleaves kininogens and fibrinogen. J Biol Chem 1993;268:7935-7942.
75.
Hosotaki K, Imamura T, Potempa J, Kitamura N, Travis J: Activation of protein C by arginine-specific cysteine proteinases (gingipains-R) from Porphyromonas gingivalis. Biol Chem 1999;380:75-80.
76.
Kaminishi H, Cho T, Itoh T, Iwata A, Kawasaki K, Hagihara Y, et al: Vascular permeability enhancing activity of Porphyromonas gingivalis protease in guinea pigs. FEMS Microbiol Lett 1993;114:109-114.
77.
Nguyen KA, Travis J, Potempa J: Does the importance of the C-terminal residues in the maturation of RgpB from Porphyromonas gingivalis reveal a novel mechanism for protein export in a subgroup of gram-negative bacteria? J Bacteriol 2007;189:833-843.
78.
Hosotaki K, Imamura T, Potempa J, Kitamura N, Travis J: Activation of protein C by arginine-specific cysteine proteinases (gingipains-R) from Porphyromonas gingivalis. Biol Chem 2005;380:75-80.
79.
Shi Y, Ratnayake B, Okamoto K, Abe N, Yamamoto K, Nakayama, K: Genetic analyses of proteolysis, hemoglobin binding, and hemagglutination of Porphyromonas gingivalis. Construction of mutants with a combination of rgpA, rgpB, kgp, and hagA. J Biol Chem 1999;274:17955-17960.
© 2015 S. Karger AG, Basel
2015
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.