The therapeutic potential of lactoferrin

Lactoferrin (Lf), a natural defence iron-binding protein, is present in exocrine secretions that are commonly exposed to normal flora: milk, tears, nasal exudate, saliva, bronchial mucus, gastrointestinal fluids, cervicovaginal mucus and seminal fluid. Additionally, Lf is produced in polymorphonuclear leukocytes and is deposited by these circulating cells in septic sites. A principal function of Lf is that of scavenging non-protein-bound iron in body fluids and inflamed areas so as to suppress free radical-mediated damage and decrease accessibility of the metal to invading bacterial, fungal and neoplastic cells. Adequate sources of bovine and recombinant human Lf are now available for development of commercial applications. Among the latter are use of Lf in food preservation, fish farming, infant milk formula and oral hygiene. Other readily accessible body compartments for Lf administration include skin, throat and small intestine. Further research is needed for possible medicinal use in colon and systemic tissues. Although Lf is a natural product and should be highly biocompatible, possible hazards have been documented.