title: Effect of interleukin-6 deficiency on the formation of periapical lesions after pulp exposure in mice.
abstract: OBJECTIVE
  The multifunctional cytokine interleukin-6 (IL-6) has actions on multiple cell types, including promotion of the development of immune cells and osteoclasts. Periapical inflammation as the result of root canal infection is characterized by the accumulation of inflammatory cells and bone resorption. The effect of IL-6 on periapical lesion formation after pulpal infection is unknown. We sought to determine whether deletion of IL-6 affects periapical lesion formation after pulp exposure.
  
  
  METHODS
  Molar pulps of homozygous IL-6 knock-out mice (IL-6(-/-), strain B6, 129-Il6tm1Koe ) and wild-type mice (IL-6(+/+)) were exposed, and the mice were killed at 1, 2, 3, 5, and 8 weeks after the exposure. Mouse jaws were decalcified and prepared for histologic examination of periapical lesions.
  
  
  RESULTS
  The IL-6(-/-) mice developed larger periapical lesions more rapidly than did the IL-6(+/+) mice.
  
  
  CONCLUSIONS
  IL-6 deletion promoted periapical lesion development.
authors.affiliation: Division of Associated Clinical Specialties, Section of Endodontics, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA. gthuang@ucla.edu
authors.forename: G T
authors.initials: GT
authors.lastname: Huang
authors.forename: M
authors.initials: M
authors.lastname: Do
authors.forename: M
authors.initials: M
authors.lastname: Wingard
authors.forename: J S
authors.initials: JS
authors.lastname: Park
authors.forename: N
authors.initials: N
authors.lastname: Chugal
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001862:Bone Resorption / Q000209:etiology; D003786:Dental Pulp Cavity / Q000473:pathology; D003789:Dental Pulp Exposure / Q000150:complications*; D004195:Disease Models, Animal; D005347:Fibroblasts / Q000473:pathology; D017353:Gene Deletion; D006720:Homozygote; D015850:Interleukin-6 / Q000172:deficiency* / Q000276:immunology; D008214:Lymphocytes / Q000473:pathology; D008264:Macrophages / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D018345:Mice, Knockout; D009154:Mutation / Q000235:genetics; D009504:Neutrophils / Q000473:pathology; D010010:Osteoclasts / Q000473:pathology; D010482:Periapical Abscess / Q000209:etiology; D010483:Periapical Diseases / Q000209:etiology* / Q000276:immunology; D010484:Periapical Granuloma / Q000209:etiology; D010485:Periapical Periodontitis / Q000209:etiology; D013223:Statistics as Topic
chemical_list: D015850:Interleukin-6