Lactoferrin inhibits early steps of human BK polyomavirus infection

Lactoferrin, a member of the transferrin family, is a bi-globular iron binding glycoprotein, found in milk, exocrine secretions of mammals, and in secondary granules of polymorphonuclear neutrophiles that plays an important role in the defence against various pathogenic microorganisms. Previous studies in different virus-cell systems showed that lactoferrin is a potent inhibitor of different enveloped and naked virus infection. In this research we studied the effect of lactoferrin on BK polyomavirus, a human naked double-stranded DNA virus responsible for productive, persistent, and latent infections of the urinary tract. Results obtained demonstrate that lactoferrin treatment prevents early steps of BK virus infection in Vero cells, at the level of the adsorption phase, probably through the interaction with capsidic structures, although a lactoferrin-BK virus competition for cell plasma-membrane receptors cannot be ruled out.