T cells may play an important role in Parkinson’s disease (PD), according to a study funded by the National Institutes of Health (NIH) and published recently in the journal Nature.
In the study, supported by the National Institute of Neurological Disorders and Stroke (NINDS), part of the NIH, a research team collected blood samples from 67 individuals with Parkinson’s disease and 36 healthy controls.
They then extracted immune cells from the samples and mixed them with portions of the alpha-synuclein protein, which accumulates in the brains of people with PD and can result in cell death.
According to the researchers, T cells from people with PD responded to the presence of alpha-synuclein to a much greater degree than those gathered from the control group, explains a media release from the National Institutes of Health.
In particular, two regions of alpha-synuclein evoked reactions from T cells: a section that often contains mutations linked with PD, and a portion undergoing a chemical change that can lead to accumulation of the protein in the brain.
The team identified four genetic variations that were associated with T cell reactivity to alpha-synuclein. More than half of people with PD carried at least one of those variants, compared to 20% of controls, the release continues.
“These findings expose a potential biomarker for PD that may someday help in diagnosing the disease or be used to evaluate how well treatments are working,” says Alessandro Sette, DrBiolSci, professor of infectious diseases at the La Jolla Institute for Allergy and Immunology in California, and part of the research team.
The results suggest that PD may have characteristics of an autoimmune disease, in which the immune system incorrectly attacks the body’s own cells.
“As we age, proteins throughout the body undergo various molecular modifications. If they become unrecognizable, the immune system may start going after them, thinking they may be dangerous invaders,” states David Sulzer, PhD, professor of neurology at Columbia University in New York City, and leader of the research team, per the release.
More research is needed to learn about the interactions between immune cells and alpha-synuclein. Improved understanding of those interactions may lead to information about disease progression as well as potential connections to other neurodegenerative disorders, the researchers conclude.
[Source: National Institutes of Health]