title: Expression of matrilin-2 and -4 in human dental pulps during dentin-pulp complex wound healing.
abstract: BACKGROUND
  Matrilin-2 and matrilin-4 are members of the matrilin family displaying broad tissue distribution. We recently reported that matrilin-2 showed significant down-regulation during the odontogenic differentiation of dental pulp cells (DPCs). It is reported that matrilin-4 was the only extracellular matrix biogenesis and organization-related gene detected in odontoblasts but not DPCs. However, the exact role of matrlin-2 and -4 in dental pulps remains unclear. The aim of our study was to analyze the expression of matrilin-2 and -4 in human dental pulps and their relation to dentin-pulp complex wound healing.
  
  
  METHODS
  Immunohistology was performed on the paraffin-embedded tissue sections of human dental pulps from sound and deep carious teeth. Matrilin-2 and -4 messenger RNAs were detected by quantitative real-time reverse-transcription polymerase chain reaction, and the proteins were shown by immunofluorescence and Western blot during odontogenic differentiation of the DPCs.
  
  
  RESULTS
  In the sound dental pulp, matrilin-2 immunoreactivity was observed throughout the pulp, whereas matrilin-4 was observed only in the odontoblast layer. In deep carious dental pulp, matrilin-2 protein was weakly stained, whereas matrilin-4 was detected in the pulp under the carious lesion. During odontogenic differentiation of DPCs, the expression of matrilin-2 messenger RNA was down-regulated within 14 days followed by a statistical increase on day 21, and the matrilin-2 protein level was down-regulated within the 3 weeks, whereas the messenger RNA and protein expressions of matrilin-4 increased in a time-dependent manner.
  
  
  CONCLUSIONS
  Matrilin-2 and matrilin-4 have been shown in human dental pulps and might be involved in the dentin-pulp complex wound-healing process.
authors.affiliation: Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Chanchan
authors.initials: C
authors.lastname: Chen
authors.forename: Xi
authors.initials: X
authors.lastname: Wei
authors.forename: Junqi
authors.initials: J
authors.lastname: Ling
authors.forename: Nan
authors.initials: N
authors.lastname: Xie
mesh_terms: D000293:Adolescent; D000328:Adult; D015153:Blotting, Western; D002454:Cell Differentiation / Q000502:physiology; D003731:Dental Caries / Q000473:pathology; D003782:Dental Pulp / Q000166:cytology*; D003804:Dentin / Q000166:cytology; D015536:Down-Regulation; D016326:Extracellular Matrix Proteins / Q000032:analysis*; D005455:Fluorescent Antibody Technique; D015870:Gene Expression; D006023:Glycoproteins / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry; D064235:Matrilin Proteins; D009804:Odontoblasts / Q000166:cytology; D009805:Odontogenesis / Q000502:physiology; D010750:Phosphoproteins / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012795:Sialoglycoproteins / Q000032:analysis; D013997:Time Factors; D014945:Wound Healing / Q000502:physiology; D055815:Young Adult; D000099311:Dentin Sialophosphoprotein
chemical_list: D016326:Extracellular Matrix Proteins; D006023:Glycoproteins; D064235:Matrilin Proteins; D010750:Phosphoproteins; D012333:RNA, Messenger; D012795:Sialoglycoproteins; D000099311:Dentin Sialophosphoprotein; C577541:MATN2 protein, human; C577548:MATN4 protein, human