Fig. 3: Blocking PGE2 signaling via the EP2 receptor increases AM numbers in aged mice.

aâc Aged (18â22 months) C57BL/6 mice were given 7 daily i.p. injections of an EP2 antagonist. Concurrently, BrdU (0.8âmg/mL) was given in the drinking water ad libitum. AMs (i.e., CD45+ CD11c+ SiglecF+) were then collected from the BALF and analyzed by flow cytometry for BrdU incorporation, indicating proliferation, and Annexin V staining, indicating apoptosis. a Total cell count of lavaged AMs. nâ=â6/group. b Percentage of AMs that are BrdU+. nâ=â5/group. c Percentage of AMs that are Annexin V+. nâ=â6/group. dâf Aged mice were given clodronate-loaded liposomes to deplete resident AMs prior to an adoptive transfer of CFSE+ WT or EP2 KO AMs as depicted in (d). e, f AMs were analyzed by flow cytometry 4 weeks following transfer for CFSE dilution, a marker of proliferation nâ=â6/group. f Representative histogram of CFSE MFI. For panels aâe, statistical significance analyzed by MannâWhitney, error bars represent SEM and each point represents a biological replicate. Source data are provided as a Source Data file.