Transcript of the December 2023 Guerrerio/“ASCI Perspectives” video

Interview with Pamela A. Guerrerio, MD, PhD, National Institute of Allergy and Infectious Diseases, NIH (elected 2020)
Interviewed by Jennifer S. Yu, MD, PhD (elected 2022), member, ASCI Diversity, Equity, and Inclusion Committee

Note: The text has been edited for readability by ASCI staff.

Jennifer S. Yu: Good morning and welcome to ASCI Perspectives. I am Jennifer Yu from the Cleveland Clinic, and I have here with me Dr. Pamela Guerrerio. Dr. Guerrerio is a Senior Investigator in Chief of the Laboratory of Allergic Diseases and Chief of the Food Allergy Research Section at the National Institutes of Health. Her research has focused on understanding genetic, immunologic, and biochemical determinants that lead to the development of food allergies. Her work informs how we may improve patient care.

Given the rising prevalence and severity of food allergies, her research is timely and much needed. Dr. Guerrerio has received a number of awards for her research, including the Art Trust Faculty Development Award from the American Academy of Asthma, Allergy, and Immunology, and the Presidential Early Career Award for Scientists and Engineers. She was inducted into the ASCI in 2022. Dr. Guerrerio, welcome, and thank you for taking the time to speak with us today.

Pamela A. Guerrerio: Thank you, Jennifer.

JSY: My pleasure. Can you share with us your path to becoming a physician-scientist? Was there something in particular that attracted you to this career path?

PAG: Yeah, so I grew up on a farm in Iowa, and I went to the University of Iowa for college. I was fortunate as an undergraduate to be able to do research all four years, which I absolutely loved. So when my advisor told me about a combined MD-PhD program, I thought it was just the perfect fit for what I wanted to do. So after I finished college, I came to the East Coast and did my MD-PhD at Johns Hopkins. I stayed at Hopkins to do my residency in pediatrics and then a fellowship in allergy and immunology. And that’s really when I became interested in food allergy. Growing up, I can’t say that I knew anyone who had a food allergy, and now this disease affects almost one in every 13 children. I found it just unbelievable that something as essential to life as eating could be potentially deadly to nearly 8% of children living in this country. So since then, my research career has really been focused on food allergy and understanding why some children develop this disease and what we can do to improve their clinical care.

JSY: Thank you. So can you talk to us about some of the factors that might be contributing to this increase in prevalence of food allergies and why is it that some people develop food allergies whereas others don’t?

PAG: That’s a great question. Something I spend a lot of time thinking about. I think at this point, the development of food allergy involves both a genetic predisposition as well as exposure to triggers in the environment. If you are a child and you have a parent or a sibling who has peanut allergy, you are seven times more likely to develop peanut allergy than someone with no family history. So genes clearly play a role. However, this rise in food allergy prevalence has been relatively recent, only over the last several decades. And so our gene pool doesn’t change that quickly. Genetics can’t be the whole explanation. I think there’s a number of factors in the environment that may play a role. There’s a number of studies pointing to vitamin D deficiency. We know that infants that are born in the fall and winter months are more likely to develop food allergy than infants who are born in the spring and the summer.

There’s been several studies showing that the farther you go from the equator where there’s less UV light exposure, the greater the number of EpiPen prescriptions and hospitalizations for food allergy. And that was true independent of longitude. And then I think some of the best evidence actually comes out of Australia, where they looked at over 5,000 infants and found that those who were vitamin D deficient were 12 times more likely to develop peanut allergy than the infants who had normal vitamin D levels.

And then I think there’s also a great deal of evidence accumulating that the microbiome plays an important role. We know that infants who grow up on a farm, those that have multiple older siblings, or those that have a pet — specifically a dog — growing up, seem to be protected from developing food allergy, whereas those that receive antibiotics early in life or born by C-section may be at higher risk.

There’s been several groups now that have looked more directly at the composition and function of bacteria and other microbes in the intestine of allergic and nonallergic infants. And there clearly are differences. There’s been some groups that have even taken stool from allergic and healthy infants and colonized germ-free mice, and they concluded that allergic infants are missing bacteria that can protect against the development of food allergy. So taken all together, I think there are likely multiple environmental factors that are acting on a genetically predisposed host that is leading to this rise in food allergy.

JSY: Very interesting. Thank you for sharing. For our early-career colleagues who will see this interview, do you have a few words of wisdom or lessons learned during your career journey?

PAG: I think the first thing I would tell them is I cannot imagine a more rewarding or fulfilling career. Personally, I can’t imagine doing anything else. But in terms of advice, I think the first thing I would say is to try and enjoy the process. The training to be a physician-scientist can seem long, and so I think it’s important to take each day one at a time and really try to embrace each step and enjoy it. The second piece of advice, I think, would be to try and reach out, encourage, and support one another. Science is a team sport. I see it again and again in my work, and there are inevitably going to be successes and failures. So it’s important to reach out, support one another along the way, no matter what stage of your career you’re at.

JSY: Well said. Thank you, Dr. Guerrerio, for taking the time to speak with us and for sharing your journey and your words of wisdom.

PAG: Thank you. It’s been an honor to be here.