The release of cytochromecfrom aging neutrophils on Western blot and densitometry. Cytoplasmic fractions were extracted from human neutrophils after 0, 3, 6, 18, and 24 hours of aging in vitro. (A) Cytosolic cytochrome c release was assessed using Western blot analysis. The blot represents one of 3 separate experiments. (B) Densitometry of the 3 blots was performed and the density of each band (percent of total pixels) expressed as mean ± SEM.