This kit is designed to precisely differentiate human and bovine osteocalcins, using a capture antibody-coated plate with a human osteocalcin-specific monoclonal antibody that recognizes the distinct difference in the amino acids at positions 3 and 4 from the N-terminus. This makes possible differential assays of human and bovine osteocalcins. Use of human antigen-specific antibody as a capture monoclonal antibody provides improved linearity when assaying human blood samples.
This specificity also enables direct assay of human osteocalcin in the culture supernatant of osteoblasts or differentiated osteoblasts from bone marrow or mesenchymal stem cells cultured in a bovine serum-containing medium.
The detection antibody in this kit specifically recognizes the gamma-carboxyglutamate (Gla) at position 17, which preferentially measures the Gla-type (active type) osteocalcin that binds to the bone matrix (primarily hydroxyapatite). Further, this kit may be used to measure osteocalcin in human blood.
Osteocalcin, also known as bone gamma-carboxyglutamate protein, is a vitamin K-and vitamin D-dependent, calcium-binding, non-collagenous protein. It has a molecular weight of approximately 5,900 and contains two or three gamma-carboxyglutamate residues (Gla). Osteocalcin is produced only by osteoblasts and their dental counterpart, odontoblasts, and is an indicator of bone metabolism. The carboxylated form of osteocalcin, in particular, is an indicator of bone formation. Osteocalcin is also a hormone that regulates glucose and fat deposition and acts as a regulator in male fertility.
