Purity > 90% as determined by SDS-PAGE. MW: 28kDa. Full Length of Mature Protein: 115-331aa. N-terminal 6xHis-tagged. Homo sapiens (Human). Thiol protease. Key protease responsible for the roval of the invariant chain from MHC class II molecules. The bond-specificity of this proteinase is in part similar to the specificities of cathepsin L and cathepsin N.