Chronic traumatic encephalopathy, a degenerative neurological disease found in the brains of athletes and others with a history of repetitive hits to the head, is hard for researchers to pin down. The disease’s prevalence is not known and it is only after death that scientists can confirm if someone was suffering from CTE.
But now, researchers believe they have identified a new biomarker for CTE, called CCL11, that could allow for a person to be diagnosed with the condition while they are still alive.
The team’s findings were published today in the journal PLOS ONE and could also help scientists distinguish CTE from Alzheimer’s disease. The two conditions have similar symptoms and are both diagnosed post-mortem.
Researchers from the VA Boston Healthcare System and the Boston University School of Medicine evaluated the brains of 23 former college and professional football players, comparing them to the brains of 50 non-athletes with Alzheimer’s disease and 18 control brains.
The team saw that CCL11 levels were normal in the control brains and in those of the non-athletes, but were significantly higher in the brains of people with CTE.
Then, the researchers compared how high the CCL11 levels were to the number of years that the athletes played football and found a positive correlation between CCL11 levels and the number of years-played.
“Not only did this research show the potential for CTE diagnosis during life, but it also offers a possible mechanism for distinguishing between CTE and other diseases. By making it possible to distinguish between normal individuals, individuals with Alzheimer’s disease, and CTE therapies can become more targeted and hopefully more effective,” first author Jonathan Cherry said in prepared remarks.
The team also took post-mortem samples of cerebrospinal fluid from four of the people in the control group, seven of the people with CTE and four of the people with Alzheimer’s disease. The researchers noted that CCL11 levels in the CSF were normal in the control group and among the people with Alzheimer’s, but were higher in the people with CTE.
“The findings of this study are the early steps toward identifying CTE during life. Once we can successfully diagnose CTE in living individuals, we will be much closer to discovering treatments for those who suffer from it,” senior author Dr. Ann McKee, director of BU’s CTE Center & chief of neuropathology at VABHS, added.
The researchers pointed out that future studies are needed to figure out if elevated levels of CCL11 are an early or late part of the CTE disease process.