title: Involvement of substance P, mast cells, TNF-alpha and ICAM-1 in the infiltration of inflammatory cells in human periapical granulomas.
abstract: BACKGROUND
  Substance P (SP), a potent proinflammatory peptide present in sensory neurons, is believed to be a major mediator of neurogenic inflammation. The aim of this study was to examine the localization and involvement of SP, mast cells and tumor necrosis factor-alpha (TNF-alpha)-positive cells in human periapical granulomas.
  
  
  METHODS
  Sections from seven periapical granulomas were stained using a variety of immunohistochemical methods.
  
  
  RESULTS
  SP-immunoreactive nerve fibers, mast cells and TNF-alpha-positive cells were found localized in the vicinity of blood vessels in all the samples of periapical granulomas. The vascular endothelial cells stained positively for E-selectin and intercellular adhesion molecule-1. SP, TNF-alpha-positive cells and E-selectin could not be detected in clinically healthy periodontal ligament, and served as a negative control.
  
  
  CONCLUSIONS
  Our findings suggest that SP, mast cells, TNF-alpha-positive cells and E-selectin may modulate the pathogenesis of apical periodontitis and may be responsible for stimulating the formation of granuloma with the resorption of periapical bone.
authors.affiliation: Department of Periodontology, Faculty of Dental Science, Kyushu University, Fukuoka 81-8582, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kabashima
authors.forename: Kengo
authors.initials: K
authors.lastname: Nagata
authors.forename: Katsumasa
authors.initials: K
authors.lastname: Maeda
authors.forename: Tadahiko
authors.initials: T
authors.lastname: Iijima
mesh_terms: D000328:Adult; D015740:Calcitonin Gene-Related Peptide / Q000096:biosynthesis; D016022:Case-Control Studies; D002634:Chemotaxis, Leukocyte; D018450:Disease Progression; D019040:E-Selectin / Q000096:biosynthesis; D004730:Endothelium, Vascular / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis; D007963:Leukocytes, Mononuclear / Q000502:physiology; D008297:Male; D008407:Mast Cells / Q000378:metabolism; D008875:Middle Aged; D020078:Neurogenic Inflammation / Q000378:metabolism*; D010484:Periapical Granuloma / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D013373:Substance P / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D019040:E-Selectin; D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1; D013373:Substance P; D015740:Calcitonin Gene-Related Peptide