Lactoferrin from bovine milk 

Lactoferrin is an iron binding protein. It is structurally similar to transferrin, the plasma iron transport protein; but lactoferrin has a much higher affinity for iron (250 fold). It is very abundant in colostrum and small amounts can also be found in tears, saliva, mucous secretions and in the secondary granules of neutrophils. It is made by mucosal epithelium and neutrophils and is released by these cells in response to inflammatory stimuli. Bacterial growth is inhibited by its ability to sequester iron and also permeabilize bacterial cell walls by binding to lipopolysaccharides through its N-terminus. Lactoferrin can inhibit viral infection by binding tightly to the viral envelope protein. This prevents cell-virus fusion by blocking the binding domain. Lactoferrin appears to activate host defense systems in part by stimulating the release of interleukin-8, a neutrophil activator. It may also be involved in antibody and interleukin synthesis, lymphocyte proliferation and complement activation.

~90% (SDS-PAGE)

mol wt ~87 kDa

cow ... LTF(280846)

2-8°C

Brock, J., Lactoferrin: a multifunctional immunoregulatory protein. Immunology Today 16, 417-419, (1995)

, Singleton, P., and Sainsbury, D. Dictionary of Microbiology and Molecular Biology 2nd ed.,, (1996)

Mann, D., et al., Delineation of the glycosaminoglycan-binding site in the human inflammatory response protein lactoferrin. J. Biol. Chem. 269, 23661-23667, (1994)

Swart, P.J., et al., Antiviral effects of milk proteins: Acylation results in polyanionic compounds with potent activity against human immunodeficiency virus types 1 and 2 in vitro. AIDS Res. Hum. Retroviruses 12, 769-775, (1996)

Harmsen, M.C., et al., Antiviral effects of plasma and milk proteins: lactoferrin shows potent activity against both human immunodeficiency virus and human cytomegalovirus replication in vitro. J. Inflamm. 172, 380-388, (1995)

Takase, M., et al., Identification of the bactericidal domain of lactoferrin. Biochim. Biophys. Acta 1121, 131-136, (1992)

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