Mig inhibits agonist-induced actin polymerization. (A) Eosinophils were treated with 10 nM eotaxin-1 (♦), 40 nM Mig (▪ and dashed line), or 40 nM Mig and 10 nM eotaxin-1 (▴) for the indicated period of time. Cells were fixed and stained with NBD-phallacidin. Relative F-actin content is expressed as the ratio of the mean channel fluorescence between eotaxin- and media alone–stimulated cells. A representative experiment is shown (n = 3). (B) Mean (± SD) percent inhibition of 10 nM PAF-induced F-actin polymerization in eosinophils in the presence of 2 to 200 nM Mig (n = 3 experiments). The analysis was performed following 10 seconds of chemokine exposure. *P < .05. (C) Actin localization was determined by fluorescence microscopy. Cells were fixed and stained with rhodamine-labeled phalloidin after stimulation for 10 seconds with buffer alone (resting), eotaxin-1 (10 nM), Mig (200 nM), or eotaxin-1 and Mig. Images were acquired with a fluorescence microscope equipped with a deconvolution system driven by Openlab software. Results are representative of 4 experiments.