SP-B deficiency causes respiratory failure in adult mice (original) (raw)

2003; 10.1152/ajplung.00011.2003.—Targeted deletion of the surfactant protein (SP)-B locus in mice causes lethal neona-tal respiratory distress. To assess the importance of SP-B for postnatal lung function, compound transgenic mice were generated in which the mouse SP-B cDNA was conditionally expressed under control of exogenous doxycycline in SP-B/ mice. Doxycycline-regulated expression of SP-B fully cor-rected lung function in compound SP-B/ mice and pro-tected mice from respiratory failure at birth. Withdrawal of doxycycline from adult compound SP-B/ mice resulted in decreased alveolar content of SP-B, causing respiratory fail-ure when SP-B concentration was reduced to25 % of normal levels. Decreased SP-B was associated with low alveolar content of phosphatidylglycerol, accumulation of mispro-cessed SP-C proprotein in the air spaces, increased protein