Protectin D1 (also known as neuroprotectin D1 when produced in neuronal tissues) is a DHA-derived dihydroxy fatty acid that exhibits potent protective and anti-inflammatory activities. 10(S),17(S)-DiHDHA is a DHA metabolite, also referred to as protectin DX (PDX). It is produced by an apparent double lipoxygenase (LO)-mediated reaction in murine peritonitis exudates, in suspensions of human leukocytes, or by soybean 15-LO incubated with DHA. It differs from protectin D1 with respect to the stereochemistry of the C-10 hydroxyl and the double bond configuration at the 13 and 15 positions. 10(S),17(S)-DiHDHA blocks neutrophil infiltration in murine peritonitis by 20-25% at a dose of 1 ng/mouse. It also inhibits platelet activation by both impairing thromboxane (TX) synthesis and TX receptor activation.