Physicists at McMaster University have identified a natural delivery system that can safely transport powerful antibiotics throughout the body to selectively attack and kill bacteria using red blood cells as a vehicle.
The platform, described in a new journal article SCA Infectious Diseases, could help solve the current antibiotic resistance crisis, say scientists. They modified and then tested red blood cells as carriers of one of the world’s last resistance-resistant antibiotics: polymyxin B (PmB), widely considered a treatment of last resort due to its toxicity and adverse effects. harmful side effects, including kidney damage.
It is used to combat particularly dangerous and often drug-resistant bacteria such as E.coliwhich is responsible for many serious diseases such as pneumonia, gastroenteritis and blood infections.
Researchers have developed a way to open up red blood cells and remove their internal components, leaving only a membrane – known as a liposome – which can be loaded with drug molecules and injected back into the body .
The process also involves coating the outside of the membrane with antibody, allowing it to stick to bacteria and safely deliver the antibody.
“Essentially, we’re using red blood cells to hide this antibiotic inside so that it can no longer interact with or harm healthy cells as it passes through the body,” says Hannah Krivic, graduate student in biophysics at McMaster and lead author. of the study. She led the work with undergraduate students Ruthie Sun and Michal Feigis, and Thode postdoctoral fellow Sebastian Himbert, all based in the Department of Physics and Astronomy.
“We designed these red blood cells to only target the bacteria we want them to target,” Krivic says.
The team, supervised by Maikel Rheinstädter, professor in the Department of Physics and Astronomy, had also focused on red blood cells in previous work (hyperlink) because they are stable, robust and have a naturally long lifespan, around 120 days, which gives them enough time to reach different target sites.
“With many traditional drug therapies, there are challenges. They tend to break down quickly as they enter our circulatory system and are randomly distributed throughout our bodies,” says Rheinstädter. “We often have to take higher doses or repeat doses, which increases drug exposure and increases the risk of side effects.”
Scientists are working on other applications of the technology, including its potential as a platform to deliver drugs across the blood-brain barrier and directly to the brain, helping patients suffering from Alzheimer’s disease or depression, for example, to receive treatment much more quickly and directly.