title: Differential human Th22-lymphocyte response triggered by Aggregatibacter actinomycetemcomitans serotypes.
abstract: OBJECTIVE
  In Aggregatibacter actinomycetemcomitans, different serotypes have been described based on lipopolysaccharide (LPS) antigenicity. When T lymphocytes were stimulated with these serotypes, different patterns of T-helper (Th)1 and Th17-type of immune responses were reported. Recently, two new Th phenotypes have been described and named Th9 and Th22 lymphocytes; however, their role in the pathogenesis of periodontitis remains unclear. This study aimed to investigate the potential Th9 and/or Th22 lymphocyte responses when stimulated with autologous dendritic cells infected with different A. actinomycetemcomitans serotypes.
  
  
  METHODS
  Monocyte-derived dendritic cells and naïve CD4+T lymphocytes were obtained from healthy donors and stimulated with different serotypes of A. actinomycetemcomitans at a multiplicity of infection MOI=102or their purified LPS (10-50ng/ml). The levels for the Th9 and Th22-associated cytokines, as well as the transcription factor master-switch genes implied in their differentiation Spi-B and AhR, were quantified by qPCR and ELISA.
  
  
  RESULTS
  When stimulated with the serotype b of A. actinomycetemcomitans, higher levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α were detected in dendritic cells, as well as higher levels of IL-22 and AhR were detected in T lymphocytes, when compared with stimulation with the other serotypes.
  
  
  CONCLUSIONS
  The serotype b of A. actinomycetemcomitans has a higher capacity of trigger Th22-type of immune response in both dendritic cells and T lymphocytes. These data allow us to suggest that, when the serotype b of A. actinomycetemcomitans is a significant part of the subgingival biofilm, the Th22 polarization might be triggered within the periodontal lesion.
authors.affiliation: Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile; Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago, Chile.
authors.forename: Jaime
authors.initials: J
authors.lastname: Díaz-Zúñiga
authors.affiliation: Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile; Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago, Chile.
authors.forename: Samanta
authors.initials: S
authors.lastname: Melgar-Rodríguez
authors.affiliation: Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Monasterio
authors.affiliation: Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile.
authors.forename: Myriam
authors.initials: M
authors.lastname: Pujol
authors.affiliation: Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile.
authors.forename: Leticia
authors.initials: L
authors.lastname: Rojas
authors.affiliation: Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile.
authors.forename: Carla
authors.initials: C
authors.lastname: Alvarez
authors.affiliation: Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago, Chile.
authors.forename: Paola
authors.initials: P
authors.lastname: Carvajal
authors.affiliation: Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile; Dentistry Unit, Faculty of Health Sciences, Universidad Autónoma de Chile, Santiago, Chile. Electronic address: rvernal@uchile.cl.
authors.forename: Rolando
authors.initials: R
authors.lastname: Vernal
mesh_terms: D016976:Aggregatibacter actinomycetemcomitans / Q000276:immunology* / Q000472:pathogenicity; D018441:Biofilms; D002454:Cell Differentiation; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D006801:Humans; D010641:Phenotype; D065288:Serogroup; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D058504:Th17 Cells; D037521:Virulence Factors
chemical_list: D016207:Cytokines; D037521:Virulence Factors
keywords: Aggregatibacter actinomycetemcomitans; T-lymphocytes; Th22 cells; Th9 cells