Administration of a potent calpain inhibitor, E-64-d, which protects PKC from proteolysis, decreases the susceptibility to Staphylococcus aureus infection in a mouse model of CHS (beige mice) [58], and improves NK and bactericidal activity in cells isolated from CHS patients in vitro [59]. This evidence concerns the gene PRRT2 and Chediak-Higashi syndrome.