A South Korean research team has developed a nanoparticle technology to eliminate viruses and bacteria from the blood of patients. The method is expected to bring new opportunities for treating infectious diseases such as COVID-19. Moreover, the unique approach could be a boon to patients infected with antibiotic-resistant bacteria.
Magnetic nanoparticles are particles of natural or synthetic materials, thousands of times smaller than the thickness of a sheet of paper. Coating the tiny particles with cell membranes camouflages them and allows them to escape the monitoring of the immune system.
Cell-camouflaged magnetic nanoparticles have been a focus of research in recent years. Most research has focused on the cells’ potential for drug delivery: particularly in cancer treatment.
The South Korean team instead focused on removing the pathogens that cause disease.
The team used nanoparticles enveloped by nanovesicles—tiny sacs that carry chemical messages between cells—derived from blood cells.
This camouflaging technique allows the nanoparticles to take on some of the functions of the blood cell membrane: in this case, that of gripping viruses and bacteria to protect the body. In addition, the technique minimizes side effects of treatment and avoids immune rejection.
When the nanoparticles are put into blood circulating outside the body, they act like magnets to attract and capture pathogens such as bacteria and viruses. The magnetic nanoparticles are then expelled from the body along with the pathogens.
The research team believes this technique will be effective for patients with sepsis or secondary bacterial infections in the intensive care unit (ICU). It also shows promise for the treatment of COVID-19 and its variants.
The team expressed its hope that the system “can provide a potential life-saving treatment method for COVID-19 patients by simultaneously reducing the SARS-CoV-2 virus and its variants, blood proinflammatory cytokines, because the deaths from COVID-19 are closely associated with the viral loads in the blood and the excessive proinflammatory cytokines in the blood.”
The study report said that new treatments using cell-camouflaged magnetic nanovesicles could eliminate “an extreme range of pathogens.” In experiments, the technique eliminated 90 to 99 percent of multi-drug-resistant bacteria and more than 135 species of bacteria present in human feces.
Experiments on rats showed that the nanoparticles can combat methicillin-resistant Staphylococcus aureus and carbapenem-resistant Escherichia coli. Researchers reported that after two treatments with the magnetic nanoparticles, “lethally infected rats” fully recovered, and their immune systems returned to normal.
Kang said the new technology mimics the human body’s innate immune response principles.
The approach “simultaneously targets a broad range of clinical isolates of various bacteria, viruses, and proinflammatory cytokines” for the first time, according to the report.
The ability to target a broad spectrum of bacteria without prior diagnosis is key, as it addresses the challenges posed by uncultured bacteria in bloodstream infections, false negative blood cultures, and limited diagnostic tools for detecting endotoxin levels.
The team said the system can be extended to treat “other infectious diseases, such as HIV and malaria infections.”
It plans to develop the technology as a new generation of infectious disease treatment technology that can rapidly respond to future epidemics of antibiotic-resistant bacteria or new infectious diseases.
