Anti-CTSK Antibody

Produced by Antibodies.com, this rabbit polyclonal primary antibody targets Cathepsin K, a lysosomal cysteine protease encoded by the CTSK gene on chromosome 1q21.3. Cathepsin K is the dominant collagenolytic enzyme secreted by activated osteoclasts during bone resorption, where it cleaves type I collagen and other matrix components at acidic pH. Germline loss-of-function mutations in CTSK cause pycnodysostosis, an autosomal recessive skeletal dysplasia characterized by short stature, acro-osteolysis of the distal phalanges, and increased bone density.

Validated for Western blot on human, mouse and rat samples, the reagent is supplied unconjugated as a 100 µl vial at 1 mg/ml in phosphate buffered saline (PBS) containing 15 mM sodium azide at approximately pH 7.2. Researchers should aliquot the antibody upon arrival and store refrigerated in the dark; for longer-term storage, freeze and limit freeze-thaw cycles to preserve binding activity. On Western blot, the mature Cathepsin K heavy chain migrates near 24 kDa, while the full-length pro-enzyme runs closer to 40 kDa.

Beyond classical bone biology, Cathepsin K expression has been documented in synovial fibroblasts, atherosclerotic plaques, thyroid tissue, and several cancer cell lines, making this antibody useful for studies in osteoporosis, rheumatoid arthritis, cardiovascular calcification, and tumor microenvironment research. Each lot is affinity-purified and quality-controlled by Antibodies.com, and the same supplier offers matched secondary antibodies and supporting reagents for full Western blot workflows.