lactoferrin
Meaning of lactoferrin: Lactoferrin is an iron binding protein in milk and other secretions that helps limit bacterial growth as part of innate immune defense.
Definition of lactoferrin
Lactoferrin is a protein that binds iron and is found in milk, tears, saliva, mucus, and certain white blood cells. Because bacteria require iron to grow and multiply, lactoferrin's ability to bind and sequester free iron helps limit the growth of bacteria in body fluids and on mucous membranes where it is present.
Beyond this iron withholding effect, lactoferrin contributes to innate immune defense through additional mechanisms, including direct effects on the outer membranes of certain bacteria, and it also functions as an antioxidant by limiting iron's ability to generate reactive, tissue damaging molecules. Lactoferrin is present in especially high concentration in colostrum, the early milk produced shortly after childbirth.
Because of its natural antimicrobial and antioxidant properties, lactoferrin derived from milk is used as an ingredient in some infant formulas and supplements, and it continues to be studied for additional roles in supporting immune function.
Used in a sentence
Lactoferrin levels were measured as part of a broader evaluation of the infant's immune status.
Good to know
Lactoferrin limits bacterial growth largely by binding iron that bacteria need to multiply, a mechanism distinct from antibodies, which target specific pathogens directly.
Word origin
Where “lactoferrin” comes from
Formed from Latin lac, meaning milk, combined with ferrum, meaning iron, reflecting the protein's origin in milk and its iron binding property.