SFTPD and acute kidney injury: To determine the role of pulmonary SP-D in pneumonia-induced AKI, firstly we compared bacterial dynamic changes in the lungs of three types (WT, KO, and hTG) of mice at 0, 6, 12, 24, 36, 48 h after intratracheal infection of bioluminescent P. aeruginosa by in vivo image method (Fig. 3A).