Figure. Concentration-dependent activation of LTB4R by LTB4. Reporter cells were transfected with either the expression plasmid for leuko­triene B4 receptor (LTB4R) or the mock plasmid and treated with various concentrations of leuko­triene B4 (LTB4). Data points shown are the mean ± SEM of an experiment performed in triplicate, and the curve is a fit to Hill equation with an EC50 of 84 pM.