In a new report published in the Journal of Dairy Science, the antiviral properties of cow milk protein against variants of SARS-CoV-2 have been investigated by scientists from the University of Michigan.

Lactoferrin is the protein in question and is found in the milk of most mammals. Bovine lactoferrin, from cow milk, has bioactive characteristics against many microbes, viruses, and other pathogens and has been found to block the ability of the virus to enter target cells, and support cells’ antiviral defense mechanisms, inhibiting SARS-CoV-2 infection under experimental conditions.

Lead investigator Jonathan Sexton, Ph.D., of the University of Michigan Department of Internal Medicine said: “Bovine lactoferrin has shown antiviral properties in human clinical trials.” “For instance, orally administered bovine lactoferrin has been demonstrated to improve the severity of viral infections, including rotavirus and norovirus. Given the minimal side effects, broad antiviral efficacy and safety, and commercial availability of bovine lactoferrin, several review papers have suggested using it as a preventive or post-exposure treatment for SARS-CoV-2 infection.”

With the goal of improving clinical relevance, the team tested bovine lactoferrin against the most common SARS-CoV-2 variants of concern, including the WA1 variant main culprit of the United States outbreak in 2020, the B.1.1.7, B.1.351, and P.1 variants, and the Delta variant, each of which includes modifications to the SARS-Cov-2 spike protein, reducing the efficacy of vaccines.

The team’s goals for this study were to give more details about the in vitro anti-SARS-CoV-2 effect of bovine lactoferrin, as well as to screen commercially available milk products for antiviral properties. Finally, they investigated whether dextrose and sorbitol, commonly used in the production of oral tablets, would interfere with the ability of bovine lactoferrin to inhibit SARS-CoV-2.

The scientists found that bovine lactoferrin was effective against all the strains that were tested in vitro, and they expect it would also have efficacy against other emergent strains. The efficacy of other components in commercial milk products does seem to be entirely dependent on bovine lactoferrin because these products did not offer antiviral activities. Moreover, the researchers found that dextrose and sorbitol did not reduce bovine lactoferrin’s effectiveness against SARS-CoV-2, suggesting the possibility of developing an anti-Covid pill.

The major benefit of lactoferrin’s antiviral efficacy is its potential for the prevention or treatment of emerging diseases. “This is especially significant when the existed treatment options are too expensive for widespread use, or there are limited options. To treat SARS-CoV-2 in areas without widespread vaccination or if new variants escape the vaccine, an orally available therapeutic that covers emerging strains would be ideal,” Sexton emphasized.
Although future work is needed to fully understand the antiviral properties of bovine lactoferrin, this study is promising in the fight against the global Covid-19 pandemic to adopt another tactic.

Reference:

https://www.dairyindustries.com/news/39706/fighting-covid-19-with-milk/