A clinical trial of a new vaccine may have found a new method to combat type 1 diabetes.

A team of researchers at the Stanford University Medical Center conducted the trial, which found that the “DNA reverse vaccine” reduced levels of immune cells linked to type 1 diabetes. It is the first demonstration of a DNA vaccine that targets type 1 diabetes in humans.

For those that received the vaccine, levels of an insulin production proxy were maintained, meaning those patients “may have” had less beta cell destruction than those who did not receive the vaccine. More importantly, blood levels of immune cells that destroy beta cell proteins were found to have been depleted in patients who receive the vaccine. The results of the trial have been published this week in the journal Science Translational Medicine.

“We’re very excited by these results, which suggest that the immunologist’s dream of shutting down just a single subset of dysfunctional immune cells without wrecking the whole immune system may be attainable,” said Dr. Lawrence Steinman, a co-author of the study and a professor neurological sciences at Stanford. “This vaccine is a new concept. It’s shutting off a specific immune response, rather than turning on specific immune responses as conventional vaccines for, say, influenza or polio aim to do.”

No DNA vaccine has yet been approved for use in humans. Researchers cautioned that the study’s results will need to be replicated in larger and longer trials, and that even then it will take years for the technology to be applied.