Hiding bacteriophages in liposomes like a Trojan horse

The liposome can become a “Trojan horse” that helps bacteriophages enter the cell and destroy intracellular bacterial pathogens

Recently, a * microfluidic technology for encapsulating bacteriophages in liposomes with a size of 100 to 300 nm was proposed in the United Kingdom. The T3 phage Escherichia coli (~ 65 nm) and the phage K Staphylococcus aureus (head size ~ 80 nm, tail length ~ 200 nm) were used as model objects in the test. The output of encapsulated bacteriophages was: for T3 – 10 9 PFU, for K – 10 5 PFU.

It was found that phage K interacts with the lipid bilayer of the liposome, resulting in a significant number of phages binding externally to the liposome instead of being enclosed within it. The authors were able to inactivate the phages outside the liposome shell while maintaining the activity of the phages inside, allowing the number of encapsulated phages to be estimated. Previously, when testing liposomes with bacteriophages, the number of encapsulated phages could be inflated due to the presence of viruses “sticking” externally to the liposome. The latter were inactivated in the acidic environment of the stomach, leading to a reduction in the phage dose reaching the target organ and, consequently, a reduction in the effectiveness of the therapy.

Encapsulating phages in nanoscale liposomes helps deliver them to human and animal cells infected with bacterial pathogens. This approach can be useful in treating infections caused by Mycobacterium tuberculosis, Listeria, Salmonella, and various Staphylococcus species.

Additionally, liposomes containing phages can be adsorbed on the surface or penetrate the mucous membranes. This is an important advantage in treating respiratory and gastrointestinal infections caused by antibiotic-resistant bacteria. Particularly in infections of the gastrointestinal tract, bacteriophages can be quickly removed from the intestine due to diarrhea, and the adhesion of liposomes to the mucous membranes interferes with this process.

* Cinquerrui S., Mancuso F., Vladisavljević GT, Bakker SE, Malik DJ. Nanoencapsulation of bacteriophages in liposomes prepared using microfluidic hydrodynamic flow focusing // Front Microbiol., 2018, 9: 2172. doi: 10.3389 / fmicb.2018.02172.

Machine translation of the source:
https://www.frontiersin.org/articles/10.3389/fmicb.2018.02172/full?report=reader