Respiratory tract antimicrobial defense system

Lactoferrin (LF) is a multifunctional protein which is an essential part of the respiratory tract antimicrobial defense system.

[6][7] The superoxide generated by these enzymes complexes dismutates into hydrogen peroxide which in turn is used by myeloperoxidase to produce bactericidal hypochlorous acid.

[8] In addition, the submucosal glands of the respiratory tract secrete myeloperoxidase and lactoperoxidase (LPO)[9] that catalyzes the oxidation of thiocyanate and detoxify hydrogen peroxide or ROS to the antimicrobial hypothiocyanite.

[12] Hypothiocyanite generated through this pathway displays broad spectrum bactericidal activity including potent antibacterial action on H.

[13] Thiocyanate secretion[14] in cystic fibrosis patients is decreased resulting in a reduced production of the antimicrobial hypothiocyanite and consequently contributes to the increased risk of airway infection.