Cathepsin W (CTSW) (CTSW)

Cathepsin W (CTSW), also known as lymphopain, is a cysteine protease belonging to the peptidase C1 family that is uniquely localized to the endoplasmic reticulum and Golgi apparatus of natural killer (NK) cells and cytotoxic T lymphocytes (CTLs) [1][2]. Unlike most other cathepsins that are ubiquitously expressed in lysosomes, Cathepsin W is restricted to the lymphoid lineage, suggesting a specialized role in the regulation of the immune system's effector functions and cell-mediated cytolytic activity [1][3]. In the context of viral infections, Cathepsin W has been identified as a host factor required for the late stages of entry and exit for viruses like the influenza A virus [4]. In oncology, high expression levels of CTSW are associated with increased immune cell infiltration and serve as a favorable prognostic biomarker in several malignancies, including breast and non-small cell lung cancers [3][5]. While specific clinical drugs targeting Cathepsin W are not yet available, its distinct expression profile makes it a compelling candidate for targeted immunotherapy or as a predictive marker for response to existing immune checkpoint inhibitors [5].

Other names

LymphopainCPWCysteine-type endopeptidase

Protease inhibition