Research Paper Volume 9, Issue 8 pp 1867—1884

p16(Ink4a) and senescence-associated β-galactosidase can be induced in macrophages as part of a reversible response to physiological stimuli

Figure 2. Macrophages elicited by alginate-encapsulated SCs possess a modulatable M2-like phenotype. Gene expression analysis of macrophage polarization markers (M1, Nos2 and Il1b; M2, Arg1) of alginate bead model (AB model)-elicited peritoneal macrophages from wild type mice via qPCR. (A) mRNA expression of Nos2 and Arg1 in AB-elicited macrophages adherence-selected from CD11b-enriched peritoneal lavage, as compared to expression in naïve bone marrow-derived macrophages (M0) or following polarization to M1 (IFN-γ for 24 hrs; M1 ctrl) or M2 (IL-4 for 24 hours; M2 ctrl) states. Gapdh expression was used an internal reference gene control. Data shows mean ± standard deviation (n=3). *** p-value < 0.001 compared to M0 control. (B) Peritoneal macrophages elicited by the alginate bead model were treated ex vivo with immunomodulatory agents. qPCR analysis of mRNA expression of indicated genes was normalized to β2-microglobulin (B2m) expression was determined following 72 hour incubation with M1-inducing stimuli (LPS at 1 ng/mL + IFN-γ at 10 ng/mL) or M2-inducing cytokines (IL-4 at 20 ng/mL + IL-13 at 10 ng/mL). Fold change in gene expression following treatment is depicted as mean ± standard deviation relative to non-treated controls; ***, p-value < 0.001. Results are representative of 3 independent experiments with peritoneal lavage cells pooled from at least 3 mice.