Surfactant protein B (SP-B)

Surfactant protein B (SP-B) is a hydrophobic, pulmonary-associated protein crucial for lung function and homeostasis following birth. Encoded by the SFTPB gene, SP-B is one of the four main surfactant proteins in the lung surfactant complex, which lines the alveoli and prevents lung collapse by regulating surface tension at the air-liquid interface. Without SP-B, alveoli stick together and collapse after exhalation, causing impaired gas exchange and severe respiratory distress. Complete SP-B deficiency, caused by mutations in the SFTPB gene, is a rare, autosomal recessive disorder that presents as lethal neonatal respiratory distress syndrome. SP-B also plays a role in lamellar body formation in lung cells and the normal processing of surfactant protein C (SP-C).

Other names

SFTPBPulmonary surfactant-associated protein BPSP-B18 kDa pulmonary-surfactant protein6 kDa proteinPSPB_HUMANPulmonary surfactant-associated proteolipid SPL(Phe)SFTP3SMDP1