Interfacial Delivery of Surfactant Protein SP-D through its Association with Pulmonary Surfactant

Abstract

Surfactant protein D (SP-D) is a glycoprotein part of the pulmonary surfactant (PS) system that carries out important roles in the innate immune defense of the lungs and participates in surfactant homeostasis. Pulmonary surfactant (PS) is a lipid-protein complex, synthesized and secreted to the alveolar space by type II pneumocytes. It spontaneously adsorbs and spreads over the air-liquid interface, reducing the surface tension and enabling the process of breathing. PS has been recently proposed as a drug delivery carrier due to its unique surface-active properties and its peculiar composition.