Rac1 activation is diminished in Jak3-inhibited or G_αi-inactivated T lymphocytes after CCL21 stimulation.

<p><i>A</i>, Representative images are shown from DMSO-, WHI-P131- or PTX-treated cells stimulated for 0, 30 and 300 seconds with CCL21. One representative cell stained with Rhodamine-phalloidin (F-actin) and Rac1-GTP Alexa-Fluor 488 (activated Rac1) is shown for each condition. <i>B</i>, The graph represents the average of mean fluorescence intensity measurements of single cells (between 5-26 cells per coverslip). An average of 36 cells per condition were individually analyzed for GTPase activation from each experiment. Data are expressed as relative increment (RI) of the fluorescence in each sample compared to unstimulated control cells. Mean values ± SEM from 3 independent experiments are shown. Asterisks indicate statistical significance (*<i>p</i><0.05).