13(S)-HODE is the LO metabolite of linoleic acid. 13(S)-HODE modulates the PAF, LTB4, and fMLP-induced calcium influx in human PMNL. The mechanism by which 13(S)-HODE elicits its inhibitory effect is still unclear. The use of biotinylated 15(S)-HETE as a probe for detecting binding proteins and/or receptors that specifically bind 15(S)-HETE provides a basis for similar use of 13(S)-HODE-biotin.