In neonatal mice, intestinal CD64 +CD206 +MHCII −macrophages do not recover one-week post-anti-CSF1 antibody injection, which affects key pro-angiogenic proteins

Abstract The small intestine of neonatal mice has abundant embryonically derived macrophages (MΦ) but only a subset remains into adulthood. These MΦ play role in fetal and development. In the intestine, they are juxtaposed to endothelial cells where facilitate postnatal vascular expansion. Postnatal recruitment bone-marrow-derived blood monocytes complicates identification study compartment since adult differentiate intestinal similar phenotype. Whether different lineages have unique roles neonates needs further investigation. To explore during period, we depleted by injecting 1-day old pups with anti-CSF1 antibodies allowed repopulate monocyte-derived for week. Flow cytometry on tissue revealed that at D8, 2.77% (± 0.32) were CD64 +CD206 +MHCII −in IgG injected compared 0.18% 0.05) (p=0.001). data show bone-marrow do not reconstitute −MΦ, which birth detected adults. We determined western blot Vegfr2 Igf1r protein expression, found be critical microvascular development, decreased 8-day 2.1-fold (p=0.047) 1.5-fold (p=0.15) respectively when littermates. Taken together, these results suggest −MΦ may their transient presence important NIH DK116568 (IDP)