Is Parkinson’s an autoimmune disease? New evidence leads towards that direction
According to a recent study published in the April 20 issue of Nature Communications, there is significant evidence indicating that Parkinson’s can be classified as an autoimmune disease. Scientists from the La Jolla Institute for Immunology discovered that such signs of autoimmunity could even be evident in Parkinson’s disease patients several years before an official diagnosis.
It is already known that the damaged protein alpha-synuclein starts forming in the dopamine-producing brain cells of patients with Parkinson’s disease. The protein eventually leads the cell to death, which in turn will trigger problems in movement, as well as cognitive decline.
Co-led by LJI professor Alessandro Sette, Dr. Biol. Sci and Professor David Sulzer, Ph.D. of the Columbia University Medical Center, the study focused on the timeline of T cell reactivity and disease progression. Comparing the blood samples of a large group of Parikinson’s disease patients to blood samples of a healthy group that matched their age led them to the following observation: T cells that react to alpha-synuclein can be found in greater quantity during the disease’s early stages. As time passes and the disease progresses, these cells disappear, with only a few patients having them up to 10 years later.
Conducting further research, the scientists analyzed the blood samples that a patient had given before his diagnosis, realizing that his T cells responded to alpha-synuclein 10 years before it was determined that he was suffering from Parkinson’s. This is a strong indicator that “detection of T cell responses could help in the diagnosis of people at risk or in early stages of disease development, when many of the symptoms have not been detected yet”, says Sette. “Importantly, we could dream of a scenario where early interference with T cell responses could prevent the disease from manifesting itself or progressing”.
Sulzer adds that “one of the most important findings is that the characteristics of the T cells change during the course of the disease, starting with more aggressive cells, moving to less aggressive cells that may inhibit the immune response, and after about 10 years, disappearing altogether.”
Interestingly, research conducted in 2018 at Friedrich-Alexander-Universitat (FAU) in Erlangen-Nurnberg, Germany, revealed that a specific type of immune T cell (Th17) attacks dopamine cells taken from people with Parkinson’s disease. However, it did not attack those that come from people without it. Senior study author Beathe Winner, a professor in the Stem Cell Biology Department of FAU had said that “we were able to clearly prove not only that (T cells) are involved in causing Parkinson’s disease, but also the role they actually play.”
As far as the researchers at LJI are concerned, they plan to use a tool called T cell-based assay, in order to figure out whether people who are at risk for Parkinson’s could be treated with therapies against inflammation from autoreactive T cells. Furthermore, they plan to observe Parkinson’s patients for longer periods of time, to understand in depth how the reactivity of T cells develops with the disease’s progression.
References:
FAU Faculty of Medicine. (2018, July 12). Retrieved April 25, 2020, from
https://www.med.fau.eu/2018/07/12/fau-researchers-identify-parkinsons-disease-as-a-possible-autoimmune-disease/
FeaturedNeurologyNeuroscienceOpen Neuroscience Articles. (2020, April 20). Further evidence autoimmunity plays a role in Parkinson’s disease. Retrieved April 25, 2020, from
https://neurosciencenews.com/parkinsons-autoimmunity-16202/
LJI Scientists Link Immune Cells to Parkinson’s Disease Onset. (2020, April 17). Retrieved April 25, 2020, from https://www.lji.org/news-events/news/post/lji-scientists-link-immune-cells-to-parkinsons-disease-
onset/.
