Lactoferrin, also known as Lactotransferrin is a glycoprotein with antimicrobial activity, both bactericidal and fungicidal, studied in the past for its inhibitory effects on HIV and cytomegalovirus, and in 2011 for the treatment of Sars.
Lactoferrin belongs to the transferrin family and has a molecular mass of 80 KDa, with two binding sites for the ferric ion (Fe3+), similar to transferrin itself.
It is mainly found in milk, but is present in many mucous secretions, and also protects newborns from infections of the gastrointestinal tract.
Lactoferrin is contained in the body in neutrophil granulocytes.
In humans, the gene coding for lactoferrin is located on chromosome 3 with location 3q21-q23.
Lactoferrin properties
The antimicrobial activity of lactoferrin is related to its affinity for Fe3+ (i.e. its high ability to compete freely with iron-dependent microorganisms), and to direct action on the outer membrane of Gram negative bacteria.
This molecule is able to remove and transport unbound iron from body fluids and phlogosis areas, thus avoiding the damage caused by toxic oxygen radicals and decreasing the presence of ferric ions.
The combination of lactoferrin with ferric ion in mucous secretions modulates the activity and aggregative capacity of bacteria and viruses towards cell membranes, this is because some bacteria require iron to carry out cell replication and lactoferrin, on the contrary, removes it from the surrounding environment, preventing its proliferation.
This protein has an iron-independent bactericidal activity, being able to attack and lysate the bacterial membrane, exploiting the affinity of its cationic domains towards the bacterial membrane (negatively charged), which, in combination with lysozyme, an enzyme capable of breaking down the β1-4 glycosidic bonds of the peptidoglycan, leads to the death of the bacterium by cytolysis.
It is also assumed to be effective against parasites, altering the membrane and weakening the bond with the host.
It is also an excellent antioxidant: it disperses excess iron and prevents the onset of oxidative stress on tissues.
During antibiotic therapies, lactoferrin can be useful to weaken bacteria against the action of drugs and, together with probiotics, increase the growth of beneficial intestinal bacterial strains (Lactobacillus or Bifidobacterium) that are less dependent on the availability of iron.
This is how it strengthens the immune defences, guaranteeing the heterogeneity of the intestinal macrobiota.
Bacteria such as Escherichia coli, however, have iron chelators that allow the micro-organism to obtain it even in the presence of lactoferrin.
The fungicidal and bactericidal power of lactoferrin (and transferrin and ovotransferrin) in vitro depends on the salt concentration. In normal fresh milk it is inactive.
Preliminary studies in treatment by Covid-19
It has been demonstrated for the first time the effectiveness of lactoferrin in favouring, without adverse effects, the disappearance of the typical symptoms of Covid-19 symptomatic positives, with the consequent negativeisation of the buffer already 12 days after treatment: the guided trial Elena Campione, of the Policlinico Tor Vergata in Rome, was published in the “International Journal of Molecular Sciences” .
The researchers administered a liposomal formulation with lactoferrin, orally and intranasally to paucisymptomatic and asymptomatic patients.
Scholars had focused their attention on lactoferrin, after noting the low incidence of covid infections in infants.
It appears that covid needs iron and lactoferrin removes it from the surrounding environment, thus acting as an antagonist.
In addition, the antiviral effect of lactoferrin is linked to its ability to bind to plasma membrane glycosaminoglycans, preventing the entry of viruses.
The study of Tor Vergata
The study conducted by the University of Tor Vergata, together with La Sapienza, was carried out on about 100 patients with mild or asymptomatic symptoms, as stated by Prof. Elena Campione, researcher involved in the study.
Some of the patients treated with lactoferrin were cured of covid in 10/12 days.
Lactoferrin proved effective in combating the symptoms of coronavirus disease in patients who were positive onset and asymptomatic.
An aspect also confirmed by the Professor of Microbiology at La Sapienza University, Piera Valenti. Dr. Valenti stated in a report on TgR, on the study of lactoferrin, that “the results obtained show that lactoferrin blocks early stages and, according to colleagues at the University of Michigan, blocks even when the cell is already infected“.
References: https://www.mdpi.com/1422-0067/21/14/4903