Increased cystatin F levels correlate with decreased cytotoxicity of cytotoxic T cells

Abstract

Cystatin F is a protein inhibitor of cysteine peptidases, expressed predominantly in immune cells and localised in endosomal/lysosomal compartments. In cytotoxic immune cells cystatin F inhibits both the major pro-granzyme convertases, cathepsins C and H that activate granzymes, and cathepsin L, that acts as perforin activator. Since perforin and granzymes are crucial molecules for target cell killing by cytotoxic lymphocytes, defects in the activation of either granzymes or perforin can affect their cytotoxic potential.

Keywords

• cystatin f
• cysteine cathepsins
• tall-104
• tgfβ
• ionomycin
• anergy