title: Comparative analysis of secretory factors from permanent- and deciduous-teeth periodontal ligament cells.
abstract: OBJECTIVE
  Studies of regenerative therapies have focused on the paracrine effects of mesenchymal stem cells, but little has been revealed about the humoral factors of periodontal ligament (PDL) stem cells. The aim of this study was to identify and compare the secretory factors of human permanent- and deciduous-teeth PDL cells (P-PDL and D-PDL cells, respectively) in order to understand the characteristics of these cells and their potential applications in regenerative therapies.
  
  
  METHODS
  Conditioned media were collected from P-PDL and D-PDL cells (P-PDL-CM and D-PDL-CM, respectively). These media were analyzed with high-performance liquid-chromatography-coupled electrospray ionization tandem mass spectrometry and a cytokine membrane assay. In addition, Western blot analysis was performed to verify the differences between the two media.
  
  
  RESULTS
  Cytokines related to neurogenesis (NT-3 and NT-4) and angiogenesis-related cytokines (EGF and IGF-1) were identified in P-PDL-CM. The expression levels of immune-response-related cytokines (interleukins I, II, and IV) and secreted proteins related to tissue degradation and catalytic activities (matrix metallopeptidase 1 (MMP1), Proteasome subunit, alpha type, 1 (PSMA1), and cullin 7 (CUL7)) were higher in D-PDL-CM. Vasorin (VASN) was expressed more strongly in P-PDL-CM, but tudor domain containing 7 (TDRD7) was expressed more strongly in D-PDL-CM in Western blot analysis.
  
  
  CONCLUSIONS
  The cytokine expressions of the two cell types showed different patterns, especially in neurogenesis and immune responses. P-PDL cells are more suitable candidates for applications in regenerative therapies.
authors.affiliation: Department of Pediatric Dentistry, Oral Science Research Center, College of Dentistry, Yonsei University, Seoul, Republic of Korea.
authors.forename: Kirim
authors.initials: K
authors.lastname: Kim
authors.affiliation: Department of Pediatric Dentistry, Oral Science Research Center, College of Dentistry, Yonsei University, Seoul, Republic of Korea.
authors.forename: Mijeong
authors.initials: M
authors.lastname: Jeon
authors.affiliation: Department of Pediatric Dentistry, College of Dentistry, Kyunghee University, Seoul, Republic of Korea.
authors.forename: Hyo-Seol
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Department of Periodontics, College of Dentistry, Dankook University, Cheonan, Republic of Korea.
authors.forename: Jung-Chul
authors.initials: JC
authors.lastname: Park
authors.affiliation: Department of Oral Biology, College of Dentistry, Yonsei University, Seoul, Republic of Korea.
authors.forename: Seok-Jun
authors.initials: SJ
authors.lastname: Moon
authors.affiliation: Department of Pediatric Dentistry, Oral Science Research Center, College of Dentistry, Yonsei University, Seoul, Republic of Korea.
authors.forename: Seong-Oh
authors.initials: SO
authors.lastname: Kim
authors.affiliation: Department of Oral Biology, College of Dentistry, Yonsei University, Seoul, Republic of Korea.
authors.forename: Sung-Won
authors.initials: SW
authors.lastname: Cho
authors.affiliation: Department of Pediatric Dentistry, Oral Science Research Center, College of Dentistry, Yonsei University, Seoul, Republic of Korea. Electronic address: songjs@yuhs.ac.
authors.forename: Je Seon
authors.initials: JS
authors.lastname: Song
mesh_terms: D000293:Adolescent; D015153:Blotting, Western; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D002851:Chromatography, High Pressure Liquid; D017077:Culture Media, Conditioned; D016207:Cytokines / Q000276:immunology* / Q000378:metabolism*; D019229:Dentition, Permanent; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010513:Periodontal Ligament / Q000166:cytology* / Q000378:metabolism*; D021241:Spectrometry, Mass, Electrospray Ionization; D014094:Tooth, Deciduous
chemical_list: D017077:Culture Media, Conditioned; D016207:Cytokines
keywords: Cytokine; Deciduous teeth; Periodontal ligament cells; Permanent teeth; Secretory factors