A new study found that in about 10% cases of multiple sclerosis, the body begins producing a distinctive set of antibodies against its own proteins years before symptoms emerge. “Multiple sclerosis is a complex autoimmune disease that is difficult to diagnose,” Colin Zamecnik, a researcher at UC San Francisco and lead author on the paper, tells Yahoo Life. “We believe that a subset of patients that go on to develop MS, around 10%, develop antibodies against a common protein domain that is prevalent in humans and viruses that infect us.”

This patient population exhibits the antibodies many years before the onset of MS. Zamecnik says that when they are tested at the time of their first disease flare, the antibodies show up in both their blood and cerebrospinal fluid. “We believe it’s possible that these patients are exhibiting cross reactive response to a prior infection, which agrees with much current work in the literature around multiple sclerosis disease progression,” he says.

Scientists already know that B cells — the cells that make antibodies — are crucial for MS disease progression. Because of this, UCSF researchers believed that profiling the antibodies in people that have, or go on to develop, MS would give them insight into the disease and reveal a possible biomarker — a measurable sign they could look out for.

“From the largest cohort of blood samples on earth, we obtained blood samples from MS patients years before their symptoms began and profiled antibodies against self — autoantibodies — that are associated with multiple sclerosis diagnosis,” says Zamecnik. “We found the first molecular marker of MS that appears up to five years before diagnosis in their blood.”

Why this is important

Although the biomarker is associated with a subset of MS patients when tested at the time of their first flare or relapse, 100% of those people exhibiting the biomarker eventually developed MS. “This could be a useful tool to help triage and diagnose patients with otherwise nonspecific neurological symptoms and prioritize them for closer surveillance and possible treatment,” says Zamecnik.

Dr. Cole Harrington, a neurologist at the Ohio State University Wexner Center, agrees that the discoveries could help diagnose MS earlier, and lead to earlier treatment.

“We do know from data in Canada looking retrospectively at people in emergency room visits and visits to health care systems, that many people have a prodromal phase of MS where they have a lot of symptoms before they’re actually diagnosed and we don’t have good biomarkers or ways of identifying people who are at risk for MS or will go on to develop MS,” says Harrington. “I think any advancement in that area will be helpful for diagnosis because the symptoms early on tend to be somewhat nonspecific.”

The biomarker could also help a category of people who have radiologically isolated syndrome, which means they have white matter changes on the brain — an indication of MS — but don’t have any classical MS relapses.

“They don’t meet criteria for MS, but some of them are at risk for developing MS, so potentially utilizing these biomarkers within that patient population may be helpful to determine which of those people are going to go on to develop MS or [have an] increased risk of developing MS,” Harrington says.

Same may occur with people who had one clinical MS relapse but don’t meet the full criteria for MS, as well as people who have relatives with MS and also have white matter changes on their brain.

“Not everybody who has a first degree relative develops MS, but the risk is higher in those individuals and so potentially applying it to those people as well with a first- or second-degree relative could be helpful,” says Harrington.

Who is at risk for MS?

According to the National Multiple Sclerosis Society, most people are diagnosed with MS between the ages of 20 and 50. However, it can occur in younger people, too. While MS can affect anyone in any ethnic group, in the U.S., the condition most commonly occurs in white people of northern European descent. MS is not believed to be passed down to relatives. However, 200 genes have been identified to contribute in a minor way to a person’s overall risk of developing MS.

Research shows that the following factors contribute to developing MS:

What are the early signs of MS?

Common symptoms of MS include the following:

Early diagnosis of MS makes a big difference

Emerging data shows earlier treatment of MS with more effective therapies is better in terms of reducing disability long-term.

“If people are not diagnosed earlier in their symptoms or have a delayed diagnosis, we are missing out on that critical therapeutic window of time where we can make a difference by suppressing the inflammation and preventing new lesions from forming,” says Harrington.

Several ongoing trials are investigating the impact of using early aggressive therapy vs. an escalation approach, which involves starting treatment with lower efficacy therapy, and moving onto more aggressive therapy when the person has a relapse or new lesion.

“I think this field is changing in terms of [scientists’] thinking and that early, more aggressive treatment is beneficial long-term for people with MS in terms of their prognosis and outcome,” Harrington says.

The best way to do this, according to Zamecnik, may be a simple antibody test that is highly specific for MS. “This signature will be the focus of future work investigating how the immune system recognizes cross talk between pathogens and self in the context of autoimmune disease,” he says.