title: Expression and correlation of matrix metalloproteinase-7 and interleukin-15 in human osteoarthritis.
abstract: OBJECTIVE
  To investigate the expression and correlation of matrix metalloproteinase (MMP)-7 and interleukin (IL)-15 in human osteoarthritis (OA).
  
  
  METHODS
  From October 2013 to December 2014, 30 patients with OA were enrolled. In addition, anther 30 patients with simple meniscus injury were collected as a control group. There were no significant differences in age and gender between the two groups. Articular cartilage tissue was obtained from both OA patients and control group patients. Protein, mRNA, and serum expression levels of MMP-7 and IL-15 in the both two groups were determined by immunohistochemical (IHC), in situ hybridization, and enzyme-linked immunosorbent assay (ELISA) assay, respectively. Additionally, correlation between MMP-7 and IL-15 expression level in cartilage tissue and serum was assessed using Pearson correlation analysis.
  
  
  RESULTS
  Protein, mRNA, and serum expression levels of MMP-7 and IL-15 in patients with OA were all significantly increased in OA patients compared with the control group. Besides, there were strong positive relationships between articular MMP-7 level and serum MMP-7 level (R(2) = 0.573, P = 0.018), between articular IL-15 level and serum IL-15 level (R(2) = 0.861, P = 0.023), and between serum IL-15 level and serum MMP-7 level (R(2) = 0.602, P = 0.012).
  
  
  CONCLUSIONS
  These results suggest that MMP-7 and IL-15 might play important roles in the pathogenesis of OA, and IL-15 and MMP-7 has positive correlation in OA.
authors.affiliation: Department of Orthopaedics, The First Clinical College of Shanxi Medical University Taiyuan, Shanxi Province, China.
authors.forename: Yulei
authors.initials: Y
authors.lastname: Tao
authors.affiliation: Guiyang Medical College Guiyang, Guizhou Province, China.
authors.forename: Xianxing
authors.initials: X
authors.lastname: Qiu
authors.affiliation: Department of Surgery, Public Health Treatment Center of Guiyang Guiyang, Guizhou Provence, China.
authors.forename: Changbo
authors.initials: C
authors.lastname: Xu
authors.affiliation: Department of Orthopaedics, Guizhou Liberation Army Hospital of The Second Group of The Third Camp, Reserve Infantry Division Guizhou Provence, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Sun
authors.affiliation: Luzhou Medical College Luzhou, Sichuan Province, China.
authors.forename: Changxiu
authors.initials: C
authors.lastname: Shi
mesh_terms: D000328:Adult; D000368:Aged; D002358:Cartilage, Articular / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D019409:Interleukin-15 / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D008297:Male; D020783:Matrix Metalloproteinase 7 / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000235:genetics / Q000378:metabolism* / Q000473:pathology
chemical_list: D019409:Interleukin-15; D020783:Matrix Metalloproteinase 7
keywords: Matrix metalloproteinase-7; interleukin-15; osteoarthritis