"What we found is that when you're depressed, it gets stuck in a gooey mess in the membrane and there is some process, and we don't understand it yet, that when you are not depressed or when an antidepressant is working, that liberates that protein and allows it to work more effectively," Rasenick explained.
A simple blood test would be able to detect the biomarker, and Rasenick believes those results may give those struggling the evidence they need to seek help.
"It would show someone, it's not just in my head, it's in my blood. The other thing is, it can help end the stigma that we have for depression," Rasenick said.
With suicide rates rising for young people during the pandemic, Dr. Sally Weinstein, a licensed clinical psychologist, said the benefit of a blood test to diagnose depression would be revolutionary.
"To have a blood test just really underscores and validates that depression has a biological origin and is a medical condition, no different from something like asthma or for diabetes," said Dr. Weinstein, who is also the Associate Director for the University of Illinois Center on Depression and Resilience.
Dr. Weinstein said it’s not mental health professionals, but primary care doctors who prescribe the majority of antidepressants.
"Primary care settings are really seen as like our first line of defense for suicide prevention. And so a tool like this, a routine, easy blood test, can really aid in that prevention strategy," Dr. Weinstein said.
The recently published study of less than 100 people found the biomarker can also track to what extent specific drug therapies, including antidepressants, are effective in individual patients.
“This is a small study, so we still have to have some reservation, but the statistics are very powerful on this small sample size suggesting there that we really do have a viable biomarker, both for depression and for antidepressant response,” Rasenick said.
Professor Rasenick and the University of Illinois Chicago are working now to expand the study and hold the clinical trials needed for FDA approval. Rasenick believes this could be the way depression is diagnosed in the future.
"If we can help get them into treatment, then we can certainly save both a lot of lives and a lot of misery," Rasenick said.