Researchers in Germany have found further evidence to support the idea that Parkinson's could be an autoimmune disease.
Autoimmune diseases arise because the immune system attacks healthy organs, tissues, and cells instead of protecting them.
There are at least 80 different known types of autoimmune disease, including rheumatoid arthritis, multiple sclerosis, lupus, and type 1 diabetes.
Although the idea that Parkinson's could be an autoimmune disease is not new, the biological evidence to back it up is only just emerging.
In 2017, for instance, a study from the U.S. revealed how pieces of a protein that builds up in the dopamine cells of people with Parkinson's can trigger a deadly immune attack against the cells.
More recently, scientists have linked the use of drugs that subdue the immune system to a lower risk of developing Parkinson's disease.
In the new study, researchers from Friedrich-Alexander-Universität (FAU) in Erlangen-Nürnberg, Germany, have shown that T helper 17 (Th17) cells — a type of immune T cell — attack dopamine cells derived from people with Parkinson's disease but not those derived from people without it.