AcylCoA:cholesterol acyltransferase (ACAT) is an intracellular cholesteryl ester synthase tied closely to the absorption of dietary cholesterol.{13122} OA is a weak inhibitor of ACAT with an IC50 of 26 μM.{12463} OA and the related glyceride dioleoyl phenylamino propane 1,2-diol have been linked to a syndrome of eosinophilia, excessive T-cell activation, and elevated IL-4, soluble IL-2R, and IL-5. The clinical consequences are an acute pulmonary inflammatory reaction followed by chronic neuropathy, myalgia, and autoimmune connective tissue disease, generally referred to as toxic oil syndrome (TOS). Aniline-denatured cooking oil is a source of OA associated with TOS.{13123}