What type of cells in the lungs are responsible for producing surfactant?

Type II cells, also known as alveolar type II cells, play a critical role in lung function by producing surfactant. Surfactant is a complex mixture of lipids and proteins that reduces surface tension within the alveoli, the small air sacs in the lungs where gas exchange occurs. The reduction of surface tension is essential because it helps to prevent the alveoli from collapsing during exhalation, thereby facilitating normal lung mechanics and ensuring efficient gas exchange.

Type II cells are located in the alveolar epithelium and account for a small portion of the total epithelial cells in the lungs. Their function in producing surfactant is vital not only for reducing surface tension but also for providing a barrier against pathogens and aiding in the repair and maintenance of the alveolar linings.

Understanding the specific roles of various lung cells is important in respiratory therapy, as conditions affecting the production or function of surfactant can lead to significant clinical issues, such as respiratory distress syndrome in neonates.