Surfactant proteins A and D (SP-A and SP-D) are members of the collectin family of
polypeptides expressed in the respiratory tract that bind bacterial, fungal and viral
pathogens, enhancing their opsonization and killing by phagocytic cells. Clearance of
bacterial pathogens including group B streptococci, Haemophilus influenza, Pseudomonas
aeruginosa and viral pathogens, respiratory syncytial virus, adenovirus and influenza A
virus, was deficient in SP-A–/–mice. SP-A deficiency was associated with enhanced …