Research Paper Volume 16, Issue 19 pp 12697—12725

Figure 1. Macrophage aging in vitro and senescence-associated phenotype. Murine peritoneal macrophages from young mice (3 months) were cultured during 2, 7 or 14 days in vitro. All results are compared to murine peritoneal macrophages from 24-month-old mice cultured for 2 days. (A) RT-qPCR analysis for p16^INK4a, p21^CIP1 and p53 transcripts normalized to 36B4 (n=13). (B) Immunoblots for p16^INK4 and p21^CIP1 at day 2, 7 and 14 (D2, D7 and D14 respectively) with quantification by densitometric analysis (n=3-4). (C) Left panel: SA-b-Gal staining for 19 hours on fixed macrophages (scale bar 20 μm). Right panel: quantification of the percentage of SA-β-gal positive cells (n=3). Error bars represent the mean ± SEM. p-values were obtained comparing groups overtime using a non-parametric one-way ANOVA analysis (Kruskal-Wallis analysis followed by Dunnett’s multiple comparison test) (*p<0.05; ****p<0.0001).