The concern is becoming such that many teams of researchers are starting to look at other alternatives to treat bacterial infections. Phage therapy which involves viruses “killers” of bacteria could well become the ultimate weapon against bacterial germs. On September 8, the civil hospices of Lyon, the second university hospital in France, launched the projet PHAG-ONE in order to develop viruses capable of eradicating ultra-resistant bacteria.
Discovery of antibiotics and antibiotic resistance
An antibiotic is a synthetic, and in some cases natural, molecule that blocks the growth of bacteria and causes their destruction. The first known antibiotic is penicillin isolated from the fungus Penicillium by Sir Alexander Fleming in 1928. However, the widespread use of antibiotics did not occur until the 1940s.
The discovery of antibiotics was one of the greatest discoveries and one of the greatest successes in modern medicine. Thanks to these molecules, medicine has been able to overcome diseases which until then caused many deaths for lack of treatment. Several families of antibiotics have been discovered and developed in particular thanks to research and progress in the field of biotechnology.
Over the years, the demand for antibiotics has accelerated with numerous therapeutic drifts such as the prescription of these molecules to patients suffering from viral infections. However, antibiotics have no effect on viruses.
Overuse of antibiotics is currently the main factor behind antibiotic resistance. This phenomenon, although natural due to the interplay of genetic mutations within bacterial cells, has greatly accelerated over the past ten years. Other factors are also at the origin of this resistance of bacteria to antibiotics: the absence of new antibiotics for about ten years, which has allowed many bacterial strains to get used to the molecules existing on the market; premature stopping of prescribed treatments, because many patients do not continue treatment to the end when it is essential; the agri-food sector, which uses many antibiotics for the treatment of animals found in human food.
>> Read also: “Antibiotic resistance: the war can be won! »
Bacteriophages, bacteria-killing viruses
Discovered in 1917 by Félix d’Hérelle, a researcher at the Institut Pasteur in Paris, bacteriophages or “bacteria eaters” are viruses which only infect bacteria (prokaryotic cells) and are, according to our current knowledge, harmless to cells. human and animal. These viral particles are found in abundance in nature, both in soil and in water.
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A bacteriophage injects its DNA into the cytoplasm of a bacterium.
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Like all viruses, bacteriophages are unable to reproduce on their own. This is why they have to get inside a living cell to hijack its genetic program. To use the cellular machinery, bacteriophages attach themselves to the bacterial wall thanks to the presence of receptors on the target bacteria. They then inject their genetic material, DNA or RNA, into the bacterial cytoplasm. It is these receptors that usually cause a given bacteriophage species to infect only one type of cell. It is therefore a weapon that makes it possible to precisely target and destroy certain bacteria.
Once inside the bacteria, the viral DNA or viral RNA filaments as well as the phage proteins are reproduced thousands of times by the host bacteria which eventually burst and expel millions of bacteriophages. This cycle is rapid and occurs millions of times until the bacteria are completely eliminated.
The use of bacteriophages in France today
With its long experience in the field of bacterial killer phages, the Eliava Institute in Georgia is the only center in the world to hold a bank of more than 6000 bacteriophages. It provides effective treatments to many eastern countries like Poland or Russia. Depending on the infectious pathology to be treated, these are oral pills, eye drops for conjunctivitis, ointments applied to the skin or aerosols for pulmonary infections.
In these countries, the use of phage therapy is a common treatment that gives good results to treat infectious diseases according to the Eliava institute. The treatment is a personalized mixture of several phages administered in a single dose, after a thorough study of the patient’s pathology.
And in France ? The legislation represents a major obstacle to the use of bacteriophages, while phage therapy appears to be a solution to antibiotic resistance. Until 2012, the use of bacteriophages to treat infectious diseases was strictly prohibited. It is now possible under a temporary authorization for personal use and on a case-by-case basis.
If France is so reluctant to authorize the use of bacteriophages, it is because no clinical study has so far been carried out. Indeed, the bacteriophages produced by the Eliava Institute in Georgia do not meet European standards for drugs and treatments.
Launched on September 8, 2021, the PHAG-ONE project represents a major breakthrough. It gives hope to patients with infectious pathologies, for whom no antibiotic gives correct results. Faced with the current situation, the development of phage therapy in the treatment of infectious diseases, in addition to antibiotic therapy, is becoming increasingly important.
Sources :
“Phages, a last-ditch treatment for Mr P.”, www.chu-lyon.fr, September 15, 2021, https://www.chu-lyon.fr/les-phages-traitement-de-la-derniere-chance-pour-monsieur-p
Website of the Eliava Institute in Georgia, https://eliava-institute.org/?lang=en
Originally published on 09/26/2021
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