Chondrex: new marker of joint disease.
Chondrex, a major secretory protein of human chondrocytes and synovial fibroblasts, is increased in serum of patients with joint and cartilage disease. We have developed a sandwich-type ELISA for quantifying chondrex in serum. The interassay CVs were 2.8-3.7% and the average within-run and total CVs were 3.6% and 5.4%, respectively. The limit of detectability by linear dilution was 20 micrograms/L, recovery upon dilution was 102% +/- 5%, and analytical recovery (of added analyte) was 98% +/- 11%. The reference interval (central 90% interval) for chondrex in healthy adults was 25-95 micrograms/L. Chondrex values for patients with active rheumatoid arthritis or osteoarthritis were significantly greater than in healthy adults, inactive rheumatoid arthritis patients, and diabetes patients (P < 0.05). In patients treated with disease-modifying antirheumatic drug therapy, decreasing chondrex values reflected the clinical improvement observed in responders, whereas the values were maintained or increased in nonresponders. In conclusion, chondrex may be a useful marker in the clinical investigation of arthritis.
Harvey
S
S
Novadex, Inc., San Diego, CA 92121, USA.
Weisman
M
M
O'Dell
J
J
Scott
T
T
Krusemeier
M
M
Visor
J
J
Swindlehurst
C
C
D054392:Adipokines; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000906:Antibodies; D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000188:drug therapy; D015415:Biomarkers / Q000097:blood; D002138:Calibration; D002356:Cartilage; D000071451:Chitinase-3-Like Protein 1; D003920:Diabetes Mellitus / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D037102:Lectins; D008297:Male; D051379:Mice; D008805:Mice, Inbred A; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D010003:Osteoarthritis / Q000097:blood* / Q000188:drug therapy; D011817:Rabbits; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D054392:Adipokines; D000906:Antibodies; D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D015415:Biomarkers; C084533:CHI3L1 protein, human; D000071451:Chitinase-3-Like Protein 1; D006023:Glycoproteins; D037102:Lectins