George Hajishengallis

Summary

Affiliation: Louisiana State University Health Sciences Center
Country: USA

Publications

  1. pmc Toll-like receptor 2 mediates cellular activation by the B subunits of type II heat-labile enterotoxins
    George Hajishengallis
    Department of Microbiology, Immunology, and Parasitology, Louisiana State University, Health Sciences Center, New Orleans, LA 70119, USA
    Infect Immun 73:1343-9. 2005
  2. pmc Downregulation of the DNA-binding activity of nuclear factor-kappaB p65 subunit in Porphyromonas gingivalis fimbria-induced tolerance
    George Hajishengallis
    Department of Microbiology, Immunology, and Parasitology, Center of Excellence in Oral and Craniofacial Biology, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70119, USA
    Infect Immun 72:1188-91. 2004
  3. ncbi request reprint Intracellular signaling and cytokine induction upon interactions of Porphyromonas gingivalis fimbriae with pattern-recognition receptors
    George Hajishengallis
    Center of Excellence in Oral and Craniofacial Biology, Department of Microbiology, Immunology, and Parasitology, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70119, USA
    Immunol Invest 33:157-72. 2004
  4. pmc The Type II heat-labile enterotoxins LT-IIa and LT-IIb and their respective B pentamers differentially induce and regulate cytokine production in human monocytic cells
    George Hajishengallis
    Louisiana State University Health Sciences Center, Department of Microbiology, Immunology, and Parasitology, Center of Excellence in Oral and Craniofacial Biology, 1100 Florida Ave, Box 130, New Orleans 70119, USA
    Infect Immun 72:6351-8. 2004
  5. ncbi request reprint Inhibition of proinflammatory activities of major periodontal pathogens by aqueous extracts from elder flower (Sambucus nigra)
    Evlambia Harokopakis
    Department of Pedodontics, School of Dentistry, Center of Excellence in Oral and Craniofacial Biology, Louisiana State University Health Sciences Center, New Orleans, LA, USA
    J Periodontol 77:271-9. 2006
  6. ncbi request reprint Peptide mapping of bacterial fimbrial epitopes interacting with pattern recognition receptors
    George Hajishengallis
    Center of Excellence in Oral and Craniofacial Biology and Department of Microbiology and Immunology, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70119, USA
    J Biol Chem 280:38902-13. 2005
  7. pmc Local complement-targeted intervention in periodontitis: proof-of-concept using a C5a receptor (CD88) antagonist
    Toshiharu Abe
    Department of Microbiology, University of Pennsylvania School of Dental Medicine, Philadelphia, PA 19104, USA
    J Immunol 189:5442-8. 2012
  8. pmc Type II heat-labile enterotoxins: structure, function, and immunomodulatory properties
    George Hajishengallis
    University of Pennsylvania School of Dental Medicine, Department of Microbiology, Philadelphia, PA 19104, USA
    Vet Immunol Immunopathol 152:68-77. 2013
  9. pmc Role of complement in host-microbe homeostasis of the periodontium
    George Hajishengallis
    Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
    Semin Immunol 25:65-72. 2013
  10. ncbi request reprint Integrin activation by bacterial fimbriae through a pathway involving CD14, Toll-like receptor 2, and phosphatidylinositol-3-kinase
    Evlambia Harokopakis
    Center of Excellence in Oral and Craniofacial Biology, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70119, USA
    Eur J Immunol 35:1201-10. 2005

Collaborators

Detail Information

Publications38

  1. pmc Toll-like receptor 2 mediates cellular activation by the B subunits of type II heat-labile enterotoxins
    George Hajishengallis
    Department of Microbiology, Immunology, and Parasitology, Louisiana State University, Health Sciences Center, New Orleans, LA 70119, USA
    Infect Immun 73:1343-9. 2005
    ..TLR2-dependent activation of mononuclear cells by type II enterotoxin B subunits appears to be a novel mechanism whereby these molecules may exert their immunomodulatory and adjuvant activities...
  2. pmc Downregulation of the DNA-binding activity of nuclear factor-kappaB p65 subunit in Porphyromonas gingivalis fimbria-induced tolerance
    George Hajishengallis
    Department of Microbiology, Immunology, and Parasitology, Center of Excellence in Oral and Craniofacial Biology, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70119, USA
    Infect Immun 72:1188-91. 2004
    ..Moreover, expression of a NF-kappaB-dependent reporter gene was inhibited upon secondary stimulation with fimbriae. NF-kappaB p65 downregulation may thus contribute to induction of FimA tolerance...
  3. ncbi request reprint Intracellular signaling and cytokine induction upon interactions of Porphyromonas gingivalis fimbriae with pattern-recognition receptors
    George Hajishengallis
    Center of Excellence in Oral and Craniofacial Biology, Department of Microbiology, Immunology, and Parasitology, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70119, USA
    Immunol Invest 33:157-72. 2004
    ..gingivalis fimbriae is essential for developing molecular approaches to control P. gingivalis-induced inflammatory responses in periodontal disease and perhaps atherosclerosis...
  4. pmc The Type II heat-labile enterotoxins LT-IIa and LT-IIb and their respective B pentamers differentially induce and regulate cytokine production in human monocytic cells
    George Hajishengallis
    Louisiana State University Health Sciences Center, Department of Microbiology, Immunology, and Parasitology, Center of Excellence in Oral and Craniofacial Biology, 1100 Florida Ave, Box 130, New Orleans 70119, USA
    Infect Immun 72:6351-8. 2004
    ..Moreover, the anti-inflammatory properties of the holotoxins may serve to suppress innate immunity and promote the survival of the pathogen...
  5. ncbi request reprint Inhibition of proinflammatory activities of major periodontal pathogens by aqueous extracts from elder flower (Sambucus nigra)
    Evlambia Harokopakis
    Department of Pedodontics, School of Dentistry, Center of Excellence in Oral and Craniofacial Biology, Louisiana State University Health Sciences Center, New Orleans, LA, USA
    J Periodontol 77:271-9. 2006
    ....
  6. ncbi request reprint Peptide mapping of bacterial fimbrial epitopes interacting with pattern recognition receptors
    George Hajishengallis
    Center of Excellence in Oral and Craniofacial Biology and Department of Microbiology and Immunology, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70119, USA
    J Biol Chem 280:38902-13. 2005
    ..Elucidation of pathogen interactions with PRRs at the molecular level may glean insight into host defense mechanisms as well as into microbial strategies that subvert innate immunity...
  7. pmc Local complement-targeted intervention in periodontitis: proof-of-concept using a C5a receptor (CD88) antagonist
    Toshiharu Abe
    Department of Microbiology, University of Pennsylvania School of Dental Medicine, Philadelphia, PA 19104, USA
    J Immunol 189:5442-8. 2012
    ..These findings not only reveal a crucial cooperation between C5aR and TLR2 in periodontal inflammation but also provide proof-of-concept for local targeting of C5aR as a powerful candidate for the treatment of human periodontitis...
  8. pmc Type II heat-labile enterotoxins: structure, function, and immunomodulatory properties
    George Hajishengallis
    University of Pennsylvania School of Dental Medicine, Department of Microbiology, Philadelphia, PA 19104, USA
    Vet Immunol Immunopathol 152:68-77. 2013
    ..This review focuses on the Type II HLTs and their immunomodulatory properties which depend largely on interactions with unique gangliosides and Toll-like receptors that are not utilized by the Type I HLTs...
  9. pmc Role of complement in host-microbe homeostasis of the periodontium
    George Hajishengallis
    Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
    Semin Immunol 25:65-72. 2013
    ..Recent insights into the mechanisms of complement involvement in periodontitis have additionally provided likely targets for therapeutic intervention against this oral disease. ..
  10. ncbi request reprint Integrin activation by bacterial fimbriae through a pathway involving CD14, Toll-like receptor 2, and phosphatidylinositol-3-kinase
    Evlambia Harokopakis
    Center of Excellence in Oral and Craniofacial Biology, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70119, USA
    Eur J Immunol 35:1201-10. 2005
    ..gingivalis has been implicated...
  11. doi request reprint Expression and function of the homeostatic molecule del-1 in endothelial cells and the periodontal tissue
    Jieun Shin
    Department of Microbiology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Philadelphia, PA 19104, USA
    Clin Dev Immunol 2013:617809. 2013
    ..The reciprocal regulation between Del-1 and inflammation may contribute to optimally balance the protective and the potentially harmful effects of inflammatory cell recruitment. ..
  12. doi request reprint Aegean reflections on innate immunity
    George Hajishengallis
    Department of Microbiology, University of Pennsylvania School of Dental Medicine, Philadelphia, Pennsylvania, USA
    Nat Immunol 14:1025-9. 2013
    ..Leading scientists from around the globe gathered on the Greek island of Kos in June 2013 to discuss the latest developments in the field of innate immunity and to explore new ideas and research collaborations. ..
  13. pmc Optimization of the ligature-induced periodontitis model in mice
    Toshiharu Abe
    University of Pennsylvania School of Dental Medicine, Department of Microbiology, Philadelphia, PA 19104, USA
    J Immunol Methods 394:49-54. 2013
    ..These optimizations are expected to facilitate the use of the mouse ligature-induced periodontitis model and consequently contribute to better understanding of the immunopathological mechanisms of periodontitis. ..
  14. pmc The keystone-pathogen hypothesis
    George Hajishengallis
    Department of Microbiology, University of Pennsylvania School of Dental Medicine, Philadelphia, Pennsylvania 19104, USA
    Nat Rev Microbiol 10:717-25. 2012
    ..In this Opinion article, we critically assess the available literature that supports this hypothesis, which may provide a novel conceptual basis for the development of targeted diagnostics and treatments for complex dysbiotic diseases...
  15. ncbi request reprint Complement-targeted therapeutics in periodontitis
    George Hajishengallis
    Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
    Adv Exp Med Biol 735:197-206. 2013
    ..In this chapter, we review recent progress in the field and discuss the potential of complement-targeted therapeutics in the treatment of periodontitis...
  16. pmc Endogenous modulators of inflammatory cell recruitment
    George Hajishengallis
    Department of Microbiology, University of Pennsylvania, School of Dental Medicine, Philadelphia, PA, USA
    Trends Immunol 34:1-6. 2013
    ..Here, we propose that locally produced modulators of leukocyte recruitment may represent local homeostatic mechanisms that tissues and organs may have evolved for protection against the destructive potential of the immune system...
  17. pmc Commensal bacteria-dependent select expression of CXCL2 contributes to periodontal tissue homeostasis
    Camille Zenobia
    Department of Microbiology, University of Washington, Seattle, WA 98195, USA
    Cell Microbiol 15:1419-26. 2013
    ..This is the first evidence that the selective use of chemokine receptor ligands contributes to neutrophil homing to healthy periodontal tissue...
  18. pmc Complement-targeted therapeutics in periodontitis
    George Hajishengallis
    Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
    Adv Exp Med Biol 734:197-206. 2013
    ..In this chapter, we review recent progress in the field and discuss the potential of complement-targeted therapeutics in the treatment of periodontitis...
  19. pmc Complement and dysbiosis in periodontal disease
    George Hajishengallis
    University of Pennsylvania School of Dental Medicine, Department of Microbiology, Philadelphia, PA 19104, USA
    Immunobiology 217:1111-6. 2012
    ..Understanding the mechanisms by which P. gingivalis modulates complement function to cause dysbiosis offers new targets for complement therapeutics...
  20. ncbi request reprint Immunogenicity of Salmonella vector vaccines expressing SBR of Streptococcus mutans under the control of a T7-nirB (dual) promoter system
    Mohammad Abdus Salam
    Department of Microbiology, University of Alabama at Birmingham, 845 19th Street South, BBRB 258 5, 35294 2170, USA
    Vaccine 24:5003-15. 2006
    ..All Salmonella clones induced good anti-SBR responses following the boost on day 320...
  21. pmc Pathogen induction of CXCR4/TLR2 cross-talk impairs host defense function
    George Hajishengallis
    Division of Oral Health and Systemic Disease Department of Periodontics, University of Louisville Health Sciences Center, Louisville, KY 40292, USA
    Proc Natl Acad Sci U S A 105:13532-7. 2008
    ..However, a specific CXCR4 antagonist abrogates this immune evasion mechanism and offers a promising counterstrategy for the control of P. gingivalis periodontal or systemic infections...
  22. ncbi request reprint The A subunit of type IIb enterotoxin (LT-IIb) suppresses the proinflammatory potential of the B subunit and its ability to recruit and interact with TLR2
    Shuang Liang
    Center for Oral Health and Systemic Disease, Department of Periodontics, University of Louisville Health Sciences Center, Louisville, KY 40292, USA
    J Immunol 178:4811-9. 2007
    ..coli may suppress TLR-mediated innate immunity through the action of the enterotoxin A subunit...
  23. ncbi request reprint Ganglioside GD1a is an essential coreceptor for Toll-like receptor 2 signaling in response to the B subunit of type IIb enterotoxin
    Shuang Liang
    Center for Oral Health and Systemic Disease and Department of Periodontics, University of Louisville Health Sciences Center, Louisville, Kentucky 40292, USA
    J Biol Chem 282:7532-42. 2007
    ..These findings establish a model of TLR2 coreceptor function and, moreover, suggest novel mechanisms of adjuvanticity by non-toxic derivatives of type II enterotoxins dependent upon GD1a/TLR2 cooperative activity...
  24. pmc Porphyromonas gingivalis fimbriae proactively modulate beta2 integrin adhesive activity and promote binding to and internalization by macrophages
    George Hajishengallis
    University of Louisville Health Sciences Center, 501 South Preston Street, Room 206, Louisville, KY 40292, USA
    Infect Immun 74:5658-66. 2006
    ..gingivalis internalization within macrophages. It therefore appears that P. gingivalis proactively modulates beta2 integrin adhesive activity for intracellular uptake...
  25. ncbi request reprint Lipopolysaccharides from atherosclerosis-associated bacteria antagonize TLR4, induce formation of TLR2/1/CD36 complexes in lipid rafts and trigger TLR2-induced inflammatory responses in human vascular endothelial cells
    Martha Triantafilou
    Infection and Immunity Group, School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9QG, UK
    Cell Microbiol 9:2030-9. 2007
    ..This antagonistic activity of H. pylori or P. gingivalis LPS, as well as their TLR2 activation capability may be associated with their ability to contribute to atherosclerosis...
  26. ncbi request reprint Differential interactions of fimbriae and lipopolysaccharide from Porphyromonas gingivalis with the Toll-like receptor 2-centred pattern recognition apparatus
    George Hajishengallis
    Center for Oral Health and Systemic Disease and Department of Periodontics Endodontics, University of Louisville Health Sciences Center, Louisville, KY 40292, USA
    Cell Microbiol 8:1557-70. 2006
    ..In summary, TLR2 activation by P. gingivalis LPS or fimbriae involves differential dependence on accessory signalling or ligand-binding receptors, which may differentially influence innate immune responses...
  27. pmc Dependence of bacterial protein adhesins on toll-like receptors for proinflammatory cytokine induction
    George Hajishengallis
    Department of Oral Biology, State University of New York at Buffalo, Buffalo, New York 14214, USA
    Clin Diagn Lab Immunol 9:403-11. 2002
    ..Our data suggest that the CD14-TLR2/4 system is involved in cytokine production and tolerance induction upon interaction with certain proinflammatory bacterial protein adhesins...
  28. ncbi request reprint TLR2 transmodulates monocyte adhesion and transmigration via Rac1- and PI3K-mediated inside-out signaling in response to Porphyromonas gingivalis fimbriae
    Evlambia Harokopakis
    Center for Oral Health and Systemic Disease, University of Louisville Health Sciences Center, KY 40292, USA
    J Immunol 176:7645-56. 2006
    ..Thus, P. gingivalis fimbriae activate a novel proadhesive pathway in human monocytes, involving TLR2, Rac1, PI3K, and CD11b/CD18, which may constitute a mechanistic basis linking P. gingivalis to inflammatory atherosclerotic processes...
  29. ncbi request reprint Complement receptor 3 blockade promotes IL-12-mediated clearance of Porphyromonas gingivalis and negates its virulence in vivo
    George Hajishengallis
    Division of Oral Health and Systemic Disease Department of Periodontics, University of Louisville Health Sciences Center, Louisville, KY 40292, USA
    J Immunol 179:2359-67. 2007
    ..Therefore, CR3 blockade may represent a promising immunomodulatory approach for controlling human periodontitis and possibly associated systemic diseases...
  30. ncbi request reprint Interactions of oral pathogens with toll-like receptors: possible role in atherosclerosis
    George Hajishengallis
    Department of Oral Biology, University at Buffalo, Buffalo, New York, USA
    Ann Periodontol 7:72-8. 2002
    ....
  31. pmc Counteracting interactions between lipopolysaccharide molecules with differential activation of toll-like receptors
    George Hajishengallis
    Department of Oral Biology, State University of New York at Buffalo, 14214, USA
    Infect Immun 70:6658-64. 2002
    ..Interactions between TLR2 and TLR4 agonists may be important in the regulation of inflammatory reactions...
  32. pmc Differential activation of human gingival epithelial cells and monocytes by Porphyromonas gingivalis fimbriae
    Mehmet A Eskan
    University of Louisville School of Dentistry, 501 South Preston Street, Room 204, Louisville, KY 40292, USA
    Infect Immun 75:892-8. 2007
    ..gingivalis FimA differentially activates human monocytes and epithelial cells, perhaps reflecting different tactics used by P. gingivalis when interacting with different host cell types or a host strategy to limit inflammation...
  33. pmc Toll-like receptor 2-mediated interleukin-8 expression in gingival epithelial cells by the Tannerella forsythia leucine-rich repeat protein BspA
    Shinsuke Onishi
    Department of Oral Biology, School of Dental Medicine, University at Buffalo, State University of New York, 3435 Main St, Buffalo, NY 14214 3092, USA
    Infect Immun 76:198-205. 2008
    ..Thus, our findings suggest that BspA is an important modulator of host innate immune responses through activation of TLR2 in cooperation with TLR1...
  34. ncbi request reprint Porphyromonas gingivalis interactions with complement receptor 3 (CR3): innate immunity or immune evasion?
    George Hajishengallis
    Department of Periodontics Endodondics, Division of Oral Health and Systemic Disease, University of Louisville School of Dentistry, Louisville, KY 40292, USA
    Front Biosci 12:4547-57. 2007
    ..gingivalis for evading innate immune clearance becomes a plausible hypothesis...
  35. pmc Importance of TLR2 in early innate immune response to acute pulmonary infection with Porphyromonas gingivalis in mice
    George Hajishengallis
    Department of Periodontics Oral Health and Systemic Disease, University of Louisville Health Sciences Center, Louisville, KY 40292, USA
    J Immunol 181:4141-9. 2008
    ..Thus, although TLR2 may mediate destructive effects, as seen in models of experimental periodontitis and atherosclerosis, we have now shown that the same receptor confers protection against P. gingivalis in acute lung infection...
  36. pmc Lipid raft-dependent uptake, signalling and intracellular fate of Porphyromonas gingivalis in mouse macrophages
    Min Wang
    Department of Periodontics Oral Health and Systemic Disease, University of Louisville Health Sciences Center, Louisville, KY 40292, USA
    Cell Microbiol 10:2029-42. 2008
    ..gingivalis, although it significantly inhibited signal transduction. In summary, P. gingivalis uses macrophage lipid rafts as signalling and entry platforms, which determine its intracellular fate to the pathogen's own advantage...
  37. pmc The use of rodent models to investigate host-bacteria interactions related to periodontal diseases
    Dana T Graves
    Department of Periodontology and Oral Biology, Boston University School of Dental Medicine, Boston, MA 02118, USA
    J Clin Periodontol 35:89-105. 2008
    ....
  38. ncbi request reprint Fimbrial proteins of porphyromonas gingivalis mediate in vivo virulence and exploit TLR2 and complement receptor 3 to persist in macrophages
    Min Wang
    Department of Periodontics Oral Health and Systemic Disease, University of Louisville Health Sciences Center, Louisville, KY 40292, USA
    J Immunol 179:2349-58. 2007
    ..gingivalis that is surprisingly dependent upon minor constituents of its fimbriae, and support the concept that pathogens evolved to manipulate innate immunity for promoting adaptive fitness and thus their capacity to cause disease...