CTSS and cardiovascular disorder: In this study, we show that the exposure of macrophages directly to HOCl and HOSCN, or to LDL modified by these oxidants, decreases the activity of the lysosomal, Cys-dependent, cathepsin enzymes B and L. These enzymes play a key role in the catabolism of proteins, and have been strongly implicated in the development of cardiovascular disease, with a deficiency in the expression and inhibition of cathepsins linked with foam cell formation [3, 36].