All experiments were done with approval from the Weizmann Institute Animal Care and Use Committee. Animals were sacrificed at the age of 10 wk. Blood and pancreata samples were stained with AlexaFluor488 anti-CD45, AlexaFluor647 anti-NK1.1, and AlexaFluor647 anti-CD3 antibodies (Biolegend) and analyzed by FACS or ImageStram. The SA-β-gal and H&E stainings were performed as described (Krizhanovsky et al. 2008 (link)). To detect immune cells in tissue sections from the pancreas, the mice were subjected to a series of seven hourly intraperitoneal injections of Caerulein (50 ng/g per injection) for 2 d in a row to induce pancreatitis. Twenty-four hours after the last injection, mice were sacrificed, and pancreata were taken, fixed in 4% PFA for 5 h at room temperature, cryoprotected in 30% sucrose, and snap-frozen in OCT. Cryosections (10 µm) were then stained with the same antibodies as for FACS.