The world’s most successful parasite even “hijacks” human cells

Toxoplasmosis is a widespread infectious disease. the trigger is Toxoplasma gnoei. It is considered the world’s most successful parasite. Millions of people carry it without knowing it. Humans have been acting as the intermediate host for centuries.

Toxoplasma reprograms human immune cells

A team from Stockholm University describes in a ArticleHow pathogenic Toxoplasma takes over our immune cells and uses them for itself. The parasite, which is more precisely an arch-shaped protozoan, is actually specialized in cats. Mice, pigs and sheep generally play the role of intermediate hosts. Obviously, people got in its way by mistake.

For a long time it was not clear how toxoplasma behaves in the human body. The researchers now explain that the pathogen uses a special protein to replace the macrophobe’s cell nucleus. After this change, immune cells no longer respond as they should. The scientists observed that the transformed cells instead behaved dendritic. They moved so quickly to various organs, sometimes even to the brain. This change in cells makes it possible for the parasite to spread rapidly throughout the body. Study co-author Antonio Barragan says:

“It is amazing that the parasite is able to hijack the identity of immune cells in such a clever way. We believe the results may explain why Toxoplasma spreads so efficiently throughout the body when infecting humans and animals. Is. “

The parasite usually enters the body through food.

In the wild, toxoplasmosis is usually transmitted through rats and cats. The mouse is an intermediate host, the cats eat the mice and thus the pathogen reaches its actual target. Here it multiplies in the animal’s intestine. The rodents, in turn, consume it through contaminated feces and start the cycle all over again.

Through modern contact between humans and cats, the parasite makes its way into the human body through consumption of raw meat of free-roaming cats or intermediate hosts such as sheep, swine, and cattle. However, people who have a healthy immune system are unlikely to notice the pathogen. However, for immunocompromised people or unborn fetuses, it can become life-threatening.

picture of Lukas Jancic: Feather Pixabay