title: Lubricin in human temporomandibular joint disc: an immunohistochemical study.
abstract: OBJECTIVE
  To evaluate, immunohistochemically, the presence and distribution of lubricin in human temporomandibular joint (TMJ) discs without any degenerative changes, obtained from autopsies, in order to elucidate the TMJ lubrication system and disc tribology.
  
  
  METHODS
  Immunohistochemistry for lubricin detection was carried out on 34 TMJ discs. Any disc had signs of degenerative or inflammatory joint disease nor disc were displaced. Sections were incubated with diluted rabbit polyclonal anti-lubricin antibody and scored according to the percentage of lubricin immunopositive cells. Three different TMJ disc tissue compartments taken from the intermediate zone were analysed, namely: the central region as well as the temporal (superior) and condylar (inferior) disc surfaces. The Friedman test, was used to compare lubricin at a protein level expression, amongst the regions of disc specimens.
  
  
  RESULTS
  Staining was noted within the TMJ disc cell populations in every disc tissue sample, however, the number of disc cells immunolabelled varied according to disc tissue regions. The percentage of immunostained cells, was statistically significant lower in the central region than in each disc surface (p<0.0001), whilst any statistically significant difference was found when comparing the two surfaces one another.
  
  
  CONCLUSIONS
  Lubricin is present in several location of TMJ disc being significantly more expressed at disc surfaces than in the central part.
authors.affiliation: Department of Dentistry, Faculty of Dentistry, University of Catania, Policlinico Universitario, Italy. rleonard@unict.it
authors.forename: Rosalia
authors.initials: R
authors.lastname: Leonardi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Musumeci
authors.forename: Edoardo
authors.initials: E
authors.lastname: Sicurezza
authors.forename: Carla
authors.initials: C
authors.lastname: Loreto
mesh_terms: D000328:Adult; D002102:Cadaver; D005260:Female; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D019224:Temporomandibular Joint Disc / Q000378:metabolism*; D000099158:Proteoglycan 4
chemical_list: D006023:Glycoproteins; D000099158:Proteoglycan 4