Publication Date



Open access

Degree Type


Degree Name

Doctor of Philosophy (PHD)


Molecular Cell and Developmental Biology (Medicine)

Date of Defense


First Committee Member

Gregory E. Conner

Second Committee Member

Nevis Fregien

Third Committee Member

Theodore Lampidis

Fourth Committee Member

Roger Fenna


The lactoperoxidase (LPO) antimicrobial system has been shown to play an important role in maintaining sterile conditions in several tissues including the mammary gland, the salivary gland, and the airway. The LPO system in the airway consists of the enzyme LPO and its substrates hydrogen peroxide and an anion. LPO catalyzes the oxidation of a halide or pseudohalide ion for example SCN-or I- by hydrogen peroxide producing a product, OSCN- or OI- which have antibacterial, antifungal, and antiviral properties. In order to have a functional antimicrobial system all the components need to be present at appropriate concentrations. The LPO system has been suggested to be deficient in cystic fibrosis. There are three possible regulatory mechanism of this antimicrobial system and these involve the secretion and availability of the three components of the LPO system in the luminal fluid. The studies presented in this dissertation examine two of the possible regulatory mechanisms of the LPO system in the airway; the availability and transport of SCN- to the luminal surface, and the expression of LPO. The knowledge obtained from these studies could be utilized to develop treatments to control infection in diseases characterized by chronic infections such as cystic fibrosis.


Lactoperoxidase; Antimicrobial; Host Defense; Airway; Ion Transport; Peroxidase; Sodium Iodide Symporter