Scientists: Parasite in cat feces may hold key to treating neurological diseases

The scientists used an engineered form of Toxoplasma gondii, a common parasite found in cat feces, to deliver proteins to the brains of mice.

In the past, neurological healthcare has been limited by the difficulty of delivering targeted therapy across the blood-brain barrier and to the correct location within neurons.

Toxoplasma gondii is believed to be carried in a latent state by a third of the world’s population, and has evolved to move from the digestive tract to the brain, where it secretes its proteins into nerve cells.

It has evolved to cross the blood-brain barrier and the placenta, and poses a risk to pregnant women as it can cause miscarriage, leading to advice that pregnant mothers should avoid handling litter boxes if their cats hunt outdoors.

Most neurological conditions, including Alzheimer’s disease, Parkinson’s disease and Rett syndrome, have been linked in some way to a protein malfunction, but scientists have had difficulty addressing the problem at the source.

The possibility of using genetically modified brain parasites to deliver therapy across the blood-brain barrier has been described as “groundbreaking” and a global breakthrough, although it is still years away from becoming a reality.

International researchers led by the University of Glasgow in collaboration with Tel Aviv University wanted to determine whether the parasite could act as a vehicle to deliver drugs to brain cells affected by the disease.

The study team first had to see if they could get the parasites to effectively produce the therapeutic proteins, and then test whether the parasites were able to “spit” the proteins back into the infected brain cells.

The researchers focused on engineering the parasites to deliver the MeCP2 protein, which has already been proposed as a promising therapeutic target for Rett syndrome, a debilitating neurological disorder caused by mutations in the MeCP2 gene.

The parasite successfully produced the protein, then transported it to the target cell site in brain organs and in mouse models.

Further experiments will be conducted to engineer the parasites to die after birth, to prevent further cell damage.

The study suggests that with further research and testing, parasites could play a potential role in delivering therapeutic proteins to the brain.

Source: Independent