Trichocystatin-2 (TC-2): An endogenous inhibitor of cysteine proteinases in Trichomonas vaginalis is associated with TvCP39

- An endogenous cystain-like inhibitor, Trichocystatin-2 (TC-2), was found in Trichomonas vaginalis.
- TC-2 inhibits the proteolytic activity of several cathepsin-L like proteinases of T. vaginalis.
- This inhibitor is a cytoplasmic and lysosomal protein associated with TvCP39.
- This interaction protects host cells from the cytotoxicity of TvCP39.
- We propose that the endogenous cystatins may modulate T. vaginalis pathogenicity mediated by cysteine proteinases.