Figure 1. Animal body weight, air pouch leukocyte counts, and viability. (A) Body weight of wild-type (WT) and A2AR-knockout mice aged 3, 6 and 15 months (n = 30 per group). (B) Ly6G+ neutrophils among cells recovered from LPS-injected dorsal air pouches (n = 12 mice per group) were enumerated as described in Methods. (C) Ly6G-positive (+) neutrophil (top panel) and Ly6G-negative (-) leukocytes (bottom panel) viability was assessed as described in Methods. (n = 12 mice per group). All values are expressed as mean ± SEM. *Significantly different from 3 months within a genotype. #Significantly different from the age-matched WT group. (D-E) Cell-free exudates were analyzed for total protein and neutrophil elastase concentrations. Phosphate-buffered saline (Basal) or buffer + LPS was injected into air pouches raised on wild-type (WT) and A2AR-knockout mice (aged 3, 6 or 15 months) as described in Methods. All values are expressed as mean ± SEM for n = 12 mice per group. *Significantly different from 3 months within a genotype. #Significantly different from the age-matched WT group.