AEBSF hydrochloride is an irreversible inhibitor of serine proteases, such as chymotrypsin, kallikrein, plasmin, thrombin, and trypsin. In Vitro: AEBSF inhibits the constitutive production of Aβ by directly inhibiting β-secretase in five different human cell lines, both neural and nonneural^[1]. AEBSF, as a serine protease inhibitor, inhibits the lysis of leukemic cells by human macrophages without inhibiting macrophage secretion of TNF-α and IL-1β^[2]. AEBSF also disturbs the growth of blastocysts on endometrial cells and inhibit the adhesion of HeLa cells on HUVECs by altering the protein secretion pattern^[4]. In Vivo: AEBSF (76.8 mg/kg daily, i.p.) results in prolongation of the survival of mice that have been given a lethal T. gondii infection^[3]. AEBSF also reduces airway response and underlying inflammation in cockroach allergen-induced murine model^[4].