Localization and expression of cartilage oligomeric matrix protein by human rheumatoid and osteoarthritic synovium and cartilage.
Synovium and cartilage from patients with osteoarthritis or rheumatoid arthritis were analyzed for expression of cartilage oligomeric matrix protein. Immunostaining of synovium with antiserum to cartilage oligomeric matrix protein demonstrated positive staining in both diseases. In osteoarthritis, there was positive staining within the synovial cells and immediately subjacent connective tissue, with less intense staining in the deeper connective tissue. In rheumatoid arthritis, there was less intense staining within the synovial cells and marked intense staining in the deeper connective tissue. In situ hybridization performed with an antisense digoxigenin-labeled riboprobe to human cartilage oligomeric matrix protein confirmed the presence of cartilage oligomeric matrix protein mRNA in the cells of the synovial lining in both types of synovium. Quantitative polymerase chain reaction with a cartilage oligomeric matrix protein MIMIC demonstrated increased cartilage oligomeric matrix protein mRNA in rheumatoid cartilage and synovium as compared with osteoarthritic cartilage and synovium, respectively; mRNA levels in rheumatoid synovium were similar to those from osteoarthritic chondrocytes. As a result of the high expression of cartilage oligomeric matrix protein from rheumatoid synovium, inflammatory synovium should be considered as a potential tissue source of cartilage oligomeric matrix protein in any investigation of biological markers of cartilage metabolism. The upregulated expression of cartilage oligomeric matrix protein in inflammatory tissues suggests its in vivo regulation by cytokines.
Di Cesare
P E
PE
Musculoskeletal Research Center, Department of Orthopaedic Surgery, New York University Medical Center-Hospital for Joint Diseases, New York 10003, USA. PEDiCesare@aol.com
Fang
C
C
Leslie
M P
MP
Della Valle
C J
CJ
Gold
J M
JM
Tulli
H
H
Perris
R
R
Carlson
C S
CS
D001172:Arthritis, Rheumatoid / Q000378:metabolism*; D064236:Cartilage Oligomeric Matrix Protein; D002358:Cartilage, Articular / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism*; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007158:Immunologic Techniques; D017403:In Situ Hybridization; D064235:Matrilin Proteins; D010003:Osteoarthritis / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D013583:Synovial Membrane / Q000378:metabolism*; D014018:Tissue Distribution / Q000502:physiology
D064236:Cartilage Oligomeric Matrix Protein; D016326:Extracellular Matrix Proteins; D006023:Glycoproteins; D064235:Matrilin Proteins; D012333:RNA, Messenger; C577553:TSP5 protein, human