Surfactant protein A promoter directs the expression of Cre recombinase in brain microvascular endothelial cells of transgenic mice

Brain microvascular endothelial cells (ECs) have unique characteristics distinguished from peripheral ECs and play important roles in blood–brain barrier (BBB). To investigate the physiological control of the brain ECs, we generated a transgenic mouse line in which the expression of Cre recombinase was driven by the promoter of the mouse surfactant protein A (SP-A) gene. The Cre activity was detected in blood vessels of brain, alveolar type II cells of lung and epithelium of gland stomach. In brain ECs, the Cre activity started at embryonic day 11.5, indicating that the subpopulation of ECs in brain could be molecularly defined at early embryonic stages. The use of SP-A-Cre mice should facilitate analysis of gene function in the brain ECs.