Researchers from the Massachusetts Institute of Technology (MIT), Brigham and Women’s Hospital and Harvard Medical School have developed a new potential treatment to reverse hair loss caused by alopecia areata, an autoimmune skin disorder.

Published in Advanced Materials, the new microneedle patch delivers immune-regulating molecules to teach T cells to not attack hair follicles, leading to hair regrowth for people of all ages.

Autoimmune skin diseases are a group of conditions that occur when the body’s immune system attacks healthy skin cells, leading to inflammation, damage and other skin problems.

Affecting more than six million people in the US, alopecia areata occurs when the body’s own T cells attack hair follicles, which leads to hair loss.

The developed microneedle patch is made from hyaluronic acid crosslinked with polyethylene glycol, which can be painlessly applied to the scalp and releases drugs that can help to rebalance the immune response at the site while also collecting samples to be used to monitor the progress of the treatment.

Researchers found that the patch helped hair regrow in a study of mice that were treated every other day for three weeks and significantly reduced inflammation at the treatment site while avoiding systemic immune effects in other areas of the body.

The treated mice were also found to have had many more regulatory T cells present at the site and hair growth was maintained for several weeks after the treatment ended.

In addition, researchers grafted human skin onto mice with a humanised immune system, which induced the proliferation of regulatory T cells as well as a reduction in inflammation.

Researchers believe that this approach could also be used to treat other autoimmune skin diseases, including vitiligo, atopic dermatitis and psoriasis, and are now working to launch a company to further develop the technology.