Study progress and significance of pulmonary surfactant-associated protein A and D

Abstract

Pulmonary surfactant-associated protein A (SP-A) and SP-D belong to lectin family,have correlation with pulmonary innate immunity, combine with a variety of sugar molecules on the microorganism surfaces and intracellular nucleic acid molecules, mediate immune function, promoteclearance and localization of bacteria,viruses, fungi, and apoptotic and necrotic cells. They can interact with molecules or receptors on the immune cell surface, regulate the functions of dendritic cells, macrophages and other immune cells. Many researches about the levels of SP-A and SP-D in alveolar lavage fluid, blood and other body fluids show that SP-A and SP-D are related to multiple pulmonary inflammation, infectious diseases. In addition,researchers have found that correlated recombinant protein has a therapeutic effect on pulmonary infectious diseases mice with SP-A and SP-D defects. This review sums up the current study of SP-A and SP-D and the relationship between various diseases and them. Key words: Pulmonary surfactant-associated protein A; Pulmonary surfactant-associated protein D; Innate immunity; Inflammatory reaction; Macrophage