CTSS Antibody / Cathepsin S, 100 ug

CTSS antibody detects Cathepsin S, a lysosomal cysteine protease that degrades extracellular matrix and participates in antigen processing. The UniProt recommended name is Cathepsin S (CTSS). This proteolytic enzyme plays a central role in endosomal protein degradation and MHC class II-mediated antigen presentation, particularly within antigen-presenting cells such as macrophages and dendritic cells.

Functionally, CTSS antibody identifies a 331-amino-acid protein synthesized as an inactive proenzyme that undergoes autocatalytic cleavage to form an active mature enzyme in acidic endosomes. Cathepsin S hydrolyzes invariant chain peptides to allow loading of antigenic peptides onto MHC class II molecules, supporting adaptive immune responses. It also contributes to extracellular matrix remodeling during inflammation and immune cell migration.

The CTSS gene is located on chromosome 1q21.3 and is highly expressed in lymphoid tissues and mononuclear phagocytes. Cathepsin S activity is regulated by cystatin protease inhibitors and by pH-dependent activation within the lysosomal environment. Its stability at neutral pH distinguishes it from other cathepsins, enabling extracellular activity during inflammation.

Pathologically, excessive CTSS activity has been associated with autoimmune diseases, atherosclerosis, and cancer. Inhibiting CTSS reduces antigen presentation and inflammatory damage, making it a therapeutic target for chronic inflammatory disorders. Research using CTSS antibody supports studies in immunology, inflammation, and protease biology.

CTSS antibody is validated for western blotting, immunohistochemistry, and enzymatic assays to detect Cathepsin S in immune tissues and cultured cells. NSJ Bioreagents provides high-quality CTSS antibody reagents optimized for proteolytic enzyme and immune pathway research.

Structurally, Cathepsin S belongs to the papain family of cysteine proteases and contains a catalytic dyad of cysteine and histidine within its active site. This antibody facilitates detection and quantification of CTSS in studies of antigen processing, protease regulation, and immune signaling.