Deliberately infecting humans with a parasite that can penetrate the brain and affect our behavior doesn't sound like the dream. Yet that is the ultimate aim of Prof. Oded Rechavi and Shahar Bracha from Tel Aviv University, with Lilach Sheiner of the University of Glasgow and a large international team.
The concept: to use engineered Toxoplasma gondii parasites to deliver drugs beyond the blood-brain barrier. T. gondii has few charms from our selfish perspective.
Cats are popular pets , but for some the small potential that they may carry toxoplasma is a deal-breaker. Although the sexual cycle of toxoplasma only occurs in cats , the chief source of toxoplasmis in humans isn't cat litters – it's eating undercooked meat of any terrestrial type from chicken to horse. Fish are not considered a competent biological host for T.
gondii, but because we filth up our waterways and seas with our waste, we have managed to infect the whole food chain . Long story short, toxoplasma has gone planetwide and somewhere from 2 to 3 billion people are believed to be infected. Unusually though not uniquely among parasites, toxoplasma can pass the blood-brain barrier that protects our brains against bad things in our blood.
How it does that is still under investigation . Once inside, the parasites encyst in the brain, nerves and muscles. In this dormant, inactive condition, the parasites don't reproduce and aren't vulnerable to drugs or our immune system.
They may stay there for the duration of .