Eicosatrienoic acid accumulates in the tissues of animals fed diets deficient in both ω-3 and ω-6 fatty acids. It can be converted to 3-series cysteinyl-leukotrienes but cannot serve as a COX substrate. The kidneys from essential fatty acid deficient rats are less immunogenic when transplanted, and the metabolites of eicosatrienoic acid are believed to play a role in altering the immune status of these organs.