Figure 3.

(a) Continuous kinetic recording of a PMA-induced respiratory burst response in guinea-pig eosinophils. Purified eosinophils (2×10⁶) were treated with 500 ng/ml PMA and the absorbance change was monitored by superoxide dismutase-inhibitable reduction of cytochrome c (deducted from the trace shown here). This trace is representative of eight separate measurements. (b) Western blot analysis of Rac2 immunoreactivity in eosinophils in comparison with human PMNs. Lane 1, postnuclear supernatant from homogenized guinea-pig eosinophils (12 μg); lane 2, whole NIH 3T3 cells (10 μg); and lane 3, cytosol from human polymorphonuclear cells (10 μg). Positions of molecular weight markers are shown at left.