Dr. Janet Sparrow Receives The 2026 Paul Kayser International Award

Janet Sparrow, PhD, the Anthony Donn Professor of Ophthalmic Science at Columbia University, is internationally recognized leader in retinal research. Her work has been instrumental in advancing understanding of the retinal pigment epithelium (RPE) and its role in retinal degeneration, particularly through studies of bisretinoid lipofuscin accumulation and its impact on vision loss.

A central focus of Dr. Sparrow’s research has been the identification and characterization of bisretinoids, key components of RPE lipofuscin that form as byproducts of the visual cycle. Her discoveries have reshaped how the field understands disease mechanisms across a range of inherited and age‑related retinal disorders, and have helped guide new approaches to diagnosis and therapy. Collectively, her work has provided a foundational framework that continues to influence both basic and translational research in retinal biology.

In recognition of these enduring and transformative contributions, Dr. Sparrow has been awarded the 2026 Paul Kayser International Award in Retina Research, one of the field’s most prestigious honors. The award underscores the global impact of her work and her role in advancing fundamental understanding of retinal disease processes that ultimately affect millions of patients worldwide. First presented in 1986, the Paul Kayser International Award in Retina Research was established through a gift to the Retina Research Foundation (RRF) in honor of businessman Paul Kayser. The RRF Paul Kayser International Award recognizes outstanding achievement by a vision scientist who has made significant contributions to advancing the understanding of retinal disorders, with the ultimate goal of improving vision and preventing blindness. We spoke with Dr. Sparrow to gain deeper insight into the work for which she has been recognized.

Congratulations on receiving the Paul Kayser International Award. As a leading expert in retina research, you are no stranger to professional recognition, with honors including the Lew R Waserman Merit Award (2001), Senior Scientific Investigator Award (2007), Alcon Research Institute Award (2004), American Academy of Ophthalmology Achievement Award (2015), RPB Stein Innovation Award (2024), among others. Being so accomplished, what does this recognition mean to you at this stage in your career?

Well, it’s always gratifying to be recognized for one’s efforts and successes, even at my stage of a career. I truly appreciate every single one of these awards. Recognition can also be important from a practical standpoint, particularly when it comes to funding—one always has to think about funding because that’s what enables us to continue moving forward with our work.

What aspects of your work contributed to this award?

For several years now, we’ve been working to understand the molecular composition of the lipofuscin that forms in the retina, much of which is made up of a class of compounds known as bisretinoids. These molecules form in the photoreceptor cells as byproducts of the visual cycle and are then transferred secondarily to the retinal pigment epithelial (RPE) cells when photoreceptor outer segments are phagocytosed. The fact that bisretinoids do not remain in the photoreceptors, but instead accumulate in the RPE, suggests to me that they are toxic. Their toxicity is closely tied to their light sensitivity—if they were present in other cells in the body, this might not be as consequential, but they reside in cells that are continually exposed to light, making them highly photoreactive.

We have therefore focused on identifying and structurally characterizing members of this family of fluorophores. We’ve studied bisretinoids across various disease states, both by examining their patterns of accumulation and by quantifying their levels. In certain retinal diseases, there is a clear increase in these compounds; for example, in ABCA4‑related disease, bisretinoid accumulation begins even before clinical onset and ultimately contributes to degeneration of both RPE and photoreceptor cells.

We’ve now identified several members of this family and have spent much of our time studying their properties, particularly their light sensitivity and the biological consequences of that sensitivity, and then relating those effects back to disease processes in the retina.

In addition to their role in retinal disease, bisretinoids are also the source of fundus autofluorescence—the intrinsic autofluorescence of the retina that can be imaged clinically using 488‑nanometer excitation. Because bisretinoids are the dominant fluorophores within RPE lipofuscin, they form the basis of an imaging modality that is used routinely in clinical practice. We’ve been able to measure their accumulation and analyze the patterns they form over time—and, I have to say, it’s been a lot of fun.

What drew you to the field of retinal research and, more specifically, to studying fundus autofluorescence?

I actually completed two postdoctoral fellowships—one at Weill Cornell in Physiology and a second at Rockefeller University in Neurobiology. It was really during my time at Rockefeller that my interest in the eye evolved. I became fascinated by the natural autofluorescence observed in retinal pigment epithelial (RPE) cells and decided to pursue this line of research when I came to Columbia University.

At the time, others and I had observed this autofluorescence in RPE cells, but there was considerable confusion in the field about what these molecules constituted. How did they form? One prevailing hypothesis was that these fluorophores arose from oxidative processes. In fact, they do not. Working with Koji Nakanishi, who was then in the Chemistry Department at Columbia, we began to demonstrate that these compounds do not form from oxidative processes, but rather form through reactions between retinaldehyde—vitamin A aldehyde—and phosphatidylethanolamine, a phospholipid that is abundant in the outer segments of photoreceptor cells.

Looking back on your career, which collaborations stand out as especially meaningful, and what do you think made those scientific partnerships successful?

I would particularly acknowledge the work I’ve done to collaborate with Stephen Tsang, who has been a valued colleague and wonderful person to work with. When he first joined the department, I mentored him in the early grant-writing days, a relationship that evolved into a highly productive collaboration that has continued for many years now.

Your research has had major implications for understanding various retinal disorders, including retinitis pigmentosa (RP), ABCA4-related disease, age-related macular degeneration (AMD), and disorders originating from the dysfunction of the visual cycle. Which findings do you feel have had the most impact?

Working with François Delori at Harvard, we developed an approach to quantifying fundus autofluorescence, called quantitative fundus autofluorescence. Using this method, we looked at several disorders. For example, in retinitis pigmentosa (RP), one can see a characteristic ring pattern in fundus images. We found that this ring corresponds to a distinct increase in autofluorescence that is markedly different from what is observed in a healthy eye.

We’ve applied quantitative autofluorescence to study several other conditions as well, including inherited retinal diseases associated with peripherin/RDS mutations and BEST disease. In addition, we’ve used this approach extensively in animal models, such as the ABCA4 knockout mouse. Together, these studies have allowed us to better understand disease‑specific patterns of retinal change and have helped establish quantitative autofluorescence as a valuable tool for both clinical research and translational studies.

Are there unexpected results or turns in your research that significantly changed the direction of your research?

One unexpected finding came from the study Vitamin A deficiency by de Carvalho et al.In this study, we examined a patient who had acquired a vitamin A deficiency following bariatric surgery. Because of adjustments to the stomach and small intestine, his ability to absorb vitamin A—and other nutrients—was significantly reduced. We were particularly interested in the effect on vitamin A levels in the retina.

What we found was that not only was the amount of bisretinoid decreased, but after vitamin A therapy the fundus autofluorescence pattern was almost the reverse of what we would have expected. It seemed that the balance between bisretinoid production versus photodegradative loss had been altered.

The Paul Kayser Award recognizes a lifetime of contributions that have significantly advanced retina research. How do you hope your work will continue to influence the field over the next decade?

I hope it continues to contribute to our understanding of progression of certain retinal diseases,. A key example is ABCA4‑associated disease, where bisretinoid accumulation occurs as a direct consequence of the gene mutation. Because the photoreceptor cells are unable to efficiently handle vitamin A aldehyde, retinaldehyde becomes more promiscuous and reacts with phosphatidylethanolamine at higher rates. This leads to increased bisretinoid formation.

What we have also found, however, is that in other forms of retinal disease, increased bisretinoid formation can occur secondarily. In these cases, the initial insult may be a different gene mutation or injury that impairs photoreceptor cells, but the downstream consequence is still enhanced bisretinoid accumulation. So there may be both primary effects, as in ABCA4‑associated disease, and secondary effects that arise as a common pathway in other retinal disease models. This framework may be useful in understanding disease mechanisms and identifying points for therapeutic intervention.

What message would you like to share with the next generation of scientists, clinicians, students, and early-career scientists entering vision research?

Well, it’s not easy to pursue a career in science. You have to be prepared to work very hard – Having a laboratory is really like managing a small business. It’s not necessarily easy, but I think it can be very rewarding.

The Paul Kayser Award will be presented during the ISER XXVII Biennial Meeting of the International Society for Eye Research, taking place in Valencia, Spain this coming August. Presented biennially, the Paul Kayser Award places Dr. Janet Sparrow among an elite group of honorees, including John E. Dowling, a renowned neuroscientist at Harvard University, and Krzysztof Palczewski, a distinguished expert in the chemistry and biology of vision and Professor at University of California, Irvine.