Dr. Ann McKee, an expert in CTE, and researchers believe they may have made a breakthrough discovery. (AP)

Just days after it was revealed that Aaron Hernandez had Stage 3 chronic traumatic encephalopathy (CTE) when he died earlier this year at just 27 years old, another revelation has popped up: the researchers at Boston University School of Medicine have made a discovery that may lead to diagnosis of the disease in living football players.

Currently, CTE can be affirmatively diagnosed only posthumously.

Dr. Ann McKee, a neuropathologist who has handled the brains of dozens of former NFL, college and high school football players, called the finding, a key biomarker, “the first ray of hope” in the efforts to understand CTE.

“To me, it feels like maybe now we can start going in the other direction,” McKee said, via the Washington Post. “We’ve been going down, and everything has just gotten more and more depressing. And now, it’s like, ‘Yeah, we’re going to actually find some answers here.’”

Researchers from BU and the VA Boston Healthcare system studied the brains of 23 former football players who were diagnosed with CTE, in addition to the brains of 50 non-athletes who suffered from Alzheimer’s disease, plus 18 non-athlete control brains; their findings were published Tuesday in the journal PLOS ONE, with McKee as senior author.

The group found significantly elevated levels of CCL11, a protein related to inflammation, in the group of ex-players compared with the non-athletes. The levels were even higher in the brains of those who had played football longer.

McKee cautioned that there is more research needed, and that the BU findings are preliminary and must be validated.

Still, as McKee noted, researchers have found a reason to hope. If elevated levels of CCL11, the biomarker, are found in a living person, it could indicate the presence of CTE, and research into the prevention and treatment of the disease can begin.

“It’s a unique disease, and it’s going to have unique proteins that are modified in this disease and this is the first indication that we’ve found one of the unique proteins,” McKee said.

Of the 23 brains of former football players used in the study, 19 belonged to men who played at the professional level, including 18 who played in the NFL, and four who played in college. The age range of the men was 25 to 87 years old, with a mean age of 62.

McKee said this discovery doesn’t necessarily allow researchers to determine how early they might eventually be able to detect the disease in a living person, but two of the brains studied belonged to a 49-year-old and 53-year-old, both with Stage 2 CTE.

“Those are on the younger side and had relatively earlier CTE and we still found this elevation, so that’s really optimistic for the future,” she said. “Obviously, now we’ll go back and look at very early and young individuals and see if this is a marker of very early stage CTE.”

It has been 12 years since Dr. Bennet Omalu published a paper called “Chronic Traumatic Encephalopathy in a National League Football Player” in the journal Neurosurgery, and researchers have been studying CTE in earnest since, looking for answers.

“This has really been our purpose: to give back to future generations,” she added. “It wasn’t just to categorize the disease and to find what these individuals had when they died. It’s really to understand CTE at the molecular and biochemical level, so we can figure out ways to detect it and more importantly, treat it.”

McKee is hopeful future studies confirm these initial findings and expand on them, and that the biomarker will help distinguish CTE from Alzheimer’s disease; the two often present similar symptoms. The new finding should also silence those who have continued to doubt the existence of CTE.

“I’ve been frustrated for years that we keep discussing or debating whether or not this disease exists, whether or not it’s unique, whether it’s simply aging,” McKee said. “This is the first demonstration that shows it’s clearly not aging. It is a distinct disease, and we’re going to exploit the uniqueness of this disease to find treatment.”

The hope, McKee said, is that future studies prove that the biomarker can be found in blood tests, and maybe show whether elevated levels of CCL11 indicate a more severe case of CTE. The research will continue, of course, but there’s relief that at last there might be a breakthrough.

“This was the first finding of a really unique component in this disease compared to others and compared to controls, so yeah, it’s a eureka moment, but we don’t think it’s the end,” she said. “We think it’s the beginning.”

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