Cathepsin B is a normal lysosomal cysteine proteinase that is expressed in all cells. It is synthesized as an inactive 43 kDa pro-enzyme which,by removal of a 62 amino acid propeptide,is activated to the single-chain form of 31 kDa or the two-chain form (25 and 5 kDa subunits). Matured cathepsin B is normally localized in the lysosomes where it functions in protein turnover. Cathepsin B is also shown capable of degrading extracellular matrix proteins. Elevated levels of cathepsin B correlate with malignancy suggesting that this enzyme may be a useful prognostic marker for several types of human cancers.
应用类型
Western blotting (0.5-4 ug/ml) amd in Immunohistochemistry (10-20 ug/ml). However, the optimal conditions should be determined individually. The purified antibody detects both the proform (37-43 kDa) and the mature form (25 kDa) of cathepsin B. It reacts with human and mouse and in a lesser extent with rat samples.
免疫原
Synthetic peptide surrounding amino acid 322 of human cathepsins B