Purity: > 90% by SDS - PAGE Format: Liquid. In Phosphate Buffered Saline (pH 7.4) containing 10% glycerol.. Ctss, as known as cathepsin S isoform 2, is a lysosomal cysteine protease of the papain family. This protein plays a major role in the processing of the MHC class II-associated invariant chain. It has been implicated in the pathogenensis of several diseases such as Alzheimer s disease and degenerative disorders associated with the cells of the mononuclear phagocytic system. Also, it is less abundant in tissues than Cathepsins B, L and H. The highest levels of this protein have been found in lymph nodes, spleen and phagocytic cells. Recombinant mouse Ctss, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.