C2K77 ELISA detects cleavage of type II collagen by cathepsin K in equine articular cartilage.
Osteoarthritis Cartilage
; 25(12): 2119-2126, 2017 12.
Article
in En
| MEDLINE
| ID: mdl-28882751
ABSTRACT
OBJECTIVES:
Develop a species-specific ELISA for a neo-epitope generated by cathepsin K cleavage of equine type II collagen to (1) measure cartilage type II collagen degradation by cathepsin K in vitro, (2) identify cytokines that upregulate cathepsin K expression and (3) compare cathepsin K with matrix metalloproteinase (MMP) collagenase activity in stimulated cartilage explants and freshly isolated normal and osteoarthritic (OA) articular cartilages.DESIGN:
A new ELISA (C2K77) was developed and tested by measuring the activity of exogenous cathepsin K on equine articular cartilage explants. The ELISA was then employed to measure endogenous cathepsin K activity in cultured cartilage explants with or without stimulation by interleukin-1 beta (IL-1ß), tumour necrosis-alpha (TNF-α), oncostatin M (OSM) and lipopolysaccharide (LPS). Cathepsin K activity in cartilage explants (control and osteoarthritic-OA) and freshly harvested cartilage (control and OA) was compared to that of MMPs employing C2K77 and C1,2C immunoassays.RESULTS:
The addition of Cathepsin K to normal cartilage caused a significant increase (P < 0.01) in the C2K77 epitope release. Whereas the content of C1,2C, that reflects MMP collagenase activity, was increased in media by the addition to cartilage explants of TNF-α and OSM (P < 0.0001) or IL-1ß and OSM (P = 0.002), no change was observed in C2K77 which also unchanged in OA cartilages compared to normal.CONCLUSIONS:
The ELISA C2K77 measured the activity of cathepsin K in equine cartilage which was unchanged in OA cartilage. Cytokines that upregulate MMP collagenase activity had no effect on endogenous cathepsin K activity, suggesting a different activation mechanism that requires further study.Key words
Full text:
1
Database:
MEDLINE
Main subject:
Osteoarthritis
/
Cartilage, Articular
/
Collagen Type II
/
Cathepsin K
/
Metacarpophalangeal Joint
Type of study:
Observational_studies
/
Prognostic_studies
Limits:
Animals
Language:
En
Journal:
Osteoarthritis Cartilage
Journal subject:
ORTOPEDIA
/
REUMATOLOGIA
Year:
2017
Type:
Article