Rachana Haliyur, MD, PhD, a first year vitreoretinal fellow at the University of Michigan Kellogg Eye Center, was awarded the prestigious Evangelos S. Gragoudas Award at the 2025 Macula Society Meeting in Charlotte Harbor, FL, where she presented her work titled “Liquid biopsy for proliferative diabetic retinopathy: human vitreous single-cell transcriptomics reveals inflammatory T cell signature”.
We spoke with Dr. Haliyur about her presentation and award.
Congratulations Dr. Haliyur on the well deserved recognition!
I am very humbled to be selected by the Macula Society for the Gragoudas Award and I want to express my sincere gratitude to the selection committee and Dr. Gragoudas for this honor. I’m so grateful to my mentor, Dr. Rajesh C. Rao, for his guidance and support on this project, and to the Kellogg Eye Center Retina Department, led by Dr. Mark Johnson, for their nomination, mentorship and support throughout my training.
What what your motivation behind this study?
Diabetic retinopathy is a leading cause of blindness in the US. Interactions at the vitreo-retinal interface contribute to vision-loss in proliferative diabetic retinopathy (PDR) making understanding of the vitreous space vital to uncovering disease mechanisms. To better investigate this, we utilized a novel approach to easily collect single cells from the diluted cassette washings during vitrectomy from patients with PDR during surgery and compared this to intravenous peripheral blood collected at the same time. Using this methodology, we captured the first single-cell vitreous atlas in human PDR.
What did you find?
Our findings highlight that T cells, a critical component of adaptive immunity, constitute the highest proportion of cell types in the human PDR vitreous with activity and functional interactions distinct from those in the peripheral blood. Neutrophils are essentially absent from the PDR vitreous however innate immune populations, such as CD16+ and CD56+ populations of natural killer cells and myeloid lineage cells, can be found. Lastly, even in the setting of vitreous hemorrhage, immune cell composition and intercellular interactions in the PDR vitreous are distinct from the peripheral blood.
What would you like the retina community to take away from your findings?
This data suggests that immune shifts in the human vitreous in diabetes are not just in terms of immune cell numbers, but also immune subtypes, activity, and function. It is likely that the inflammatory changes occurring within the PDR vitreous involves pathways of T cell immune activation rather than a single or specific cytokine pathway. Furthermore, these results demonstrate the feasibility of liquid vitreous biopsies via collection of functional vitreous cell types from diluted cassette washings during vitrectomy to better understand cellular interactions of the vitreous in other retinal disease states. Further work is necessary to confirm these findings in a larger population and in comparison to patients without diabetes.
