CAMBRIDGE, MA – A groundbreaking treatment has been developed by researchers from MIT, Brigham and Women’s Hospital, and Harvard Medical School, offering hope to individuals suffering from alopecia areata, an autoimmune disorder causing hair loss across all age groups, including children.
The innovative approach involves a microneedle patch applied to the scalp, painlessly releasing drugs that recalibrate the immune response at the affected site, thereby halting the autoimmune attack that leads to hair loss.
In a pivotal study conducted on mice, the treatment demonstrated the ability to prompt hair regrowth and significantly reduce inflammation localized to the treatment area, while avoiding widespread immune effects elsewhere in the body. Researchers anticipate this method could also be adapted to address other autoimmune skin conditions such as vitiligo, atopic dermatitis, and psoriasis.
Natalie Artzi, a principal research scientist at MIT’s Institute for Medical Engineering and Science, as well as an associate professor of medicine at Harvard Medical School and Brigham and Women’s Hospital, emphasized the groundbreaking nature of this approach, stating, “Rather than suppressing the immune system, we’re now focusing on regulating it precisely at the site of antigen encounter to generate immune tolerance.”
Artzi and Jamil R. Azzi, an associate professor of medicine at Harvard Medical School and Brigham and Women’s Hospital, are senior authors of the study recently published in the journal Advanced Materials. The lead authors of the paper are Nour Younis, a postdoctoral researcher at Brigham and Women’s, and Nuria Puigmal, a postdoctoral researcher at Brigham and Women’s and former MIT research affiliate.
The researchers are now preparing to launch a company dedicated to advancing this technology, led by Puigmal, who recently received a Harvard Business School Blavatnik Fellowship.
Direct Targeting of Autoimmune Response
Alopecia areata affects over 6 million Americans and occurs when the body’s T cells attack hair follicles, leading to hair loss. Current treatments such as painful scalp injections of immunosuppressant steroids are often intolerable for patients.
While some patients receive oral immunosuppressant drugs, they can lead to widespread immune suppression and associated adverse effects.
“This approach silences the entire immune system, offering relief from inflammation symptoms but leading to frequent recurrences. Moreover, it increases susceptibility to infections, cardiovascular diseases, and cancer,” Artzi explains.
The collaboration between Artzi and Azzi stemmed from a fortuitous encounter at a working group meeting, leading to a focus on delivering drugs directly to the skin using microneedle patches. Their prior work on preventing skin transplant rejection with microneedle patches paved the way for this new treatment strategy targeting autoimmune skin disorders.
“The skin is the only organ in our body that we can see and touch, and yet when it comes to drug delivery to the skin, we revert to systemic administration. We saw great potential in utilizing the microneedle patch to reprogram the immune system locally,” Azzi elaborates.
The microneedle patches used in this study are composed of biocompatible materials, hyaluronic acid crosslinked with polyethylene glycol (PEG), allowing effective penetration of the tough outer layer of the skin.
“This polymer formulation allows us to create highly durable needles capable of effectively penetrating the skin. Additionally, it gives us the flexibility to incorporate any desired drug,” Artzi notes.
In this study, the patches were loaded with a combination of cytokines IL-2 and CCL-22, which recruit regulatory T cells to suppress inflammation and educate the immune system to cease attacking hair follicles.
Results and Future Prospects
Mice treated with the microneedle patch every other day for three weeks exhibited increased regulatory T cells at the treatment site, decreased inflammation, and hair regrowth that persisted after treatment cessation. Importantly, there were no changes observed in regulatory T cell levels in other organs, indicating localized immune modulation.
Experiments on mice with human skin grafts and a humanized immune system demonstrated similar positive outcomes, further supporting the potential of this treatment approach.
The microneedle patches are designed not only to deliver drugs but also to collect samples post-treatment for monitoring immune response progress.
The researchers are poised to advance this technology for treating alopecia areata and explore its applications for other autoimmune skin conditions.
