Figure 3. Age does not affect neutrophil granularity, size or reactive species content in the bone marrow. Neutrophils from young (3 month) and aged (22-24 month) mice were isolated from the bone marrow of both hind femurs. Cells were exposed to increasing concentrations of PMA for 45 minutes, than analyzed for granularity (A), size (B), reactive species positivity (C) and intracellular reactive species content (D). Neutrophils from the blood of naïve young and aged mice were stained for neutrophil identification markers (CD45+/CD11b+/Ly6CInt/Ly6GHi), followed by incubation with or without PMA in the presence of 1,2,3 DHR to measure changes in (E) neutrophil granularity (SSC) and (F) neutrophil size (FSC), as well as the percentage of ROS positive neutrophils (G) and intracellular ROS production (H). *p=<.05, **p=<.01, ***p=<0.001, ****p=<0.0001.