Scientists are testing new ways to deliver injections directly to the brain. The key? Using “medical parasites” to deliver the medicine directly to the patient’s brain. The parasite the researchers are testing is a common single-celled brain parasite. Because the brain is so picky about what it lets in, finding ways to treat brain disorders has always been tricky.
However, using a parasite that can wiggle its way into the brain on its own could be a unique and interesting way to deliver the therapeutic proteins needed to treat those issues directly within the brain cells, especially since the brain can be picky about which medicines it lets in, too.
The idea of using a medical parasite to deliver medicine directly to brain cells builds off an age-old concept that helped create an assortment of different vaccines. This concept is inoculation, which essentially infects the patient with a small amount of the disease or virus that you want to treat them for and then letting the body get used to fighting it.
We use this same concept today to help treat the flu and even covid-19. While pills offer convenient ways to treat many diseases and disorders, the brain often cuts off access for the medication, so we need something that can get beyond those filters and deliver the medicine directly to the affected brain cells. That’s where these parasites—called Toxoplasma—come into play.
These parasites can infect an assortment of animals and humans. The infection can occur in multiple ways—including through the ingestion of spores released in the stool of infected cats or by consuming contaminated water or food. What makes these Toxoplasma so capable as medical parasites is that they can cross the blood-brain barrier and invade brain cells.
This makes them a great delivery vehicle for medication that needs to be delivered directly to the brain. The researchers tested the idea by hijacking the system that Toxoplasma uses to secret proteins into its host cell. They then genetically engineered their own Toxoplasma to make it a hybrid protein, essentially creating a piggyback for the medication.
A study detailing their findings and what they plan to do next has been published in Nature Microbiology. We’re still a long way from actually sending parasites into patient’s brains, but it is an interesting bit of research that could prove exceptionally useful for the medical industry in the future.
