A Conversation With John Harris, MD, PhD

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Q. What part of your work gives you the most pleasure?

A. It is too difficult to pick just one! Honestly, I think it is the integration of so many different aspects of my work that brings the most pleasure. For example, I direct a vitiligo specialty clinic once a week where I diagnose and treat patients with vitiligo, and they visit from all over the world. That is an incredibly intense experience, but deeply satisfying as we walk alongside them in their journey toward improved quality of life with the disease. I also lead a large research team working on defining the pathogenesis of vitiligo, with the goal of developing new treatments for the disease. This has led to successful clinical trials that resulted in the first FDA-approved drug to reverse vitiligo, which has been exciting, as it will impact so many patients everywhere. I have also founded several companies to develop novel treatments for skin diseases. My first, Villaris Therapeutics, developed what we hope will be the first biologic for vitiligo with potentially longlasting effects. We recently signed an agreement with Incyte Corporation to acquire Villaris and lead the further development of the drug into clinical trials. I am chair of our dermatology department at UMass Chan, and I really enjoy recruiting and mentoring faculty and trainees to find their niche in our field, focus their interests, and make their own impact on patients however they can. I find this opportunity motivating as the potential impact on patients is even larger through the compounded success of others. I feel incredibly privileged to work in all these ways, and the synergy of this work is intensely exciting and satisfying.

Q. Who was your hero/mentor and why?

A. My PhD thesis mentor, Aldo Rossini, was a physician-scientist and type 1 diabetes (T1D) expert who managed patients with diabetes and directed a large research lab focused on understanding the pathogenesis of T1D. His work inspired me to study autoimmunity, but I became frustrated that we were not studying human models of T1D, but rather animal models. I suppose I always wanted to conduct translational research, but that was not a term or concept developed back then, and we did not quite have the research tools we needed to do it at the time. Beyond that, it was nearly impossible to obtain samples of the pancreas from living patients to study the disease process. So, I told him I thought I would have to study something else that would be amenable to investigation in humans. Undaunted, he encouraged me to do just that and find my own niche that would provide the necessary passion to fuel a lifelong career as a physician-scientist. Dr Rossini later introduced me to a patient who changed the course of my career. I am so grateful to him for his insight into me and my passions, as well as the foresight to mentor me into a field that was different from his own. I miss him dearly.

Q. Which patient had the most effect on your work and why?

A. This was a patient who Dr Rossini introduced to me after I finished my PhD thesis work and returned to medical school as a third-year student. I ran into Dr Rossini late one night in the hallway of the hospital when I least expected it on a busy night call. The patient was admitted to the ICU with diabetic ketoacidosis, and Dr Rossini was checking in on her as was his custom, even on late nights. He brought me to her room and suggested I perform a history and physical exam. I discovered that she not only had T1D, but also Hashimoto thyroiditis, pernicious anemia, and vitiligo. I decided then and there that I would become a dermatologist with a focus on vitiligo so I could perform research to understand the cause of autoimmunity in humans using the skin, which is highly accessible for sampling. As I mentioned previously, I always wanted to conduct translational research without even realizing what that was. Dermatology gave me the opportunity to do this, and I never looked back.

Q. What is the best piece of advice you have received and from whom?

A. A key piece of advice that I learned from my many mentors during my training is about the importance of developing relationships. This applies to finding strong mentors who care about me as a person and success in my career, as well as my colleagues who surround me, and finally the trainees who become my mentees. These relationships are critical for my development, but they are also incredibly satisfying. One aspect of this relationship building was modeled by one of my postdoctoral mentors who said that he had achieved most of his career goals and now wanted to develop and invest in me as his mentee, leaving a legacy through my work and others who he had trained. I thought that was a beautiful and selfless sentiment. I have tried to emulate this as a mentor myself, understanding that my impact will be greatly amplified through those I have supported in their own careers. This is probably the most fulfilling role I have as a physician-scientist.

Q. Which medical figure in history would you want to have a drink with and why?

A. I would love to sit with a Vaidya in India during the Iron Age. From ancient medical writings in the Rigveda and Atharvaveda texts, we know that Vaidyas treated patients with vitiligo using an ancient form of PUVA-sol. They instructed patients to chew on the black seeds of the Psoralea corylifolia plant, swallow their saliva, and then sit in the noonday sun until they were sweating. They would develop a blistering sunburn, heal, and then their vitiligo lesions would repigment. You may have guessed that the seeds of Psoralea corylifolia contained psoralens, providing the chemical component of PUVA, while the sun provided the UVA light. In addition, the ancient texts related how stigmatizing having vitiligo was, as patients and their siblings could not marry. I would love to engage with an ancient vitiligo expert to discuss developments over the past 3400 years. For 3390 of them, not much changed, but now there is a new FDA-approved topical and clinical trials are ongoing to test more novel treatments. Of course, I would ask questions about all kinds of other things that were going on at that time, but I would certainly start with vitiligo.