Colony stimulating factor-1 expression is developmentally regulated in the mouse

Colony stimulating factor-1 (CSF-1) regulates the survival, proliferation, and differentiation of mononuclear phagocytes. To determine whether CSF-1 plays a role in the perinatal development of these cells, CSF-1 protein and mRNA expression in tissues and serum from fetal/neonatal mice and their mothers was analyzed. As fetal/neonatal age increased, CSF-1 concentrations rose in liver, kidney, and lung, declined in brain and serum, and did not change in intestine and heart. Concurrently, fetal/neonatal CSF-1 concentrations were higher in liver, kidney, and serum and lower in lung, brain, intestine, and heart than maternal tissue/serum concentrations, which showed no correlations with gestational or post-partum stage. CSF-1 mRNA was detected in all tissues examined and its expression increased ill lung and heart and decreased in brain with increasing fetal/neonatal age. The developmental regulation of mouse CSF-1 expression appears to be important for mononuclear phagocyte development during this period.