New Bolton Center Kennett Square, PA
Emergencies & Appointments:
Ryan Hospital Philadelphia, PA


Assistant Professor of Translational Ophthalmology, University of Pennsylvania School of Veterinary Medicine

Research Areas: Ophthalmology, retinal diseases
PubMed Link
Contact Information:
3900 Delancey street

In-vivo assessment of natural disease history in canine models of inherited retinal degeneration and preclinical assessment of retinal therapeutic strategies.

Expertise in cSLO/OCT imaging, retinal photography, ERG, experimental design for gene therapy studies, helped designed, organized and executed dose range finding and IND-enabling studies for pharmaceutical companies such as AGTC (RPGR-XLRP disease) and IVERIC Bio (T4R-RHO disease).

I am interested in studying and understanding any types of inherited retinal disease (IRD), also referred to as Progressive Retinal Atrophy (PRA) in the dogs. Ultimately, we would love to be able to bring corrective therapeutic options to the client-owned dog population.

During my residency, I have also developed a strong interest in glaucoma surgeries including shunting procedures in the hope to preserve vision and pressure control for a long time.
I have also developed strong skills in adnexal surgeries (eyelid correction) and lacrimal surgeries (Parotid duct transposition or cyclosporine implantation).

Sato, Y., Gray, A., Takahashi, K., Dufour, V., Lutty, G., Miyadera, K., Aguirre, G. Monocular retinopathy of prematurity-like retinal vasculopathy in a dog Veterinary Ophthalmology 25: 78-84, 2022.

Miyadera, K., Santana, E., Roszak, K., Iffrig, S., Visel, M., Iwabe, S., Boyd, R. F., Bartoe, J. T., Sato, Y., Gray, A., Ripolles-Garcia, A., Dufour, V. L., Byrne, L. C., Flannery, J. G., Beltran, W. A., Aguirre, G. D. Targeting ON-bipolar cells by AAV gene therapy stably reverses LRIT3-congenital stationary night blindness Proceedings of the National Academy of Sciences of the United States of America 119: e2117038119, 2022.

Ozturk, B. E., Johnson, M. E., Kleyman, M., Turunc, S., He, J., Jabalameli, S., Xi, Z., Visel, M., Dufour, V. L., Iwabe, S., Pompeo Marinho, L. F. L., Aguirre, G. D., Sahel, J. A., Schaffer, D. V., Pfenning, A. R., Flannery, J. G., Beltran, W. A., Stauffer, W. R., Byrne, L. C. scAAVengr, a transcriptome-based pipeline for quantitative ranking of engineered AAVs with single-cell resolution Elife 10: , 2021.

Dufour, V. L., Cohen, J. A., Holle, D. M., Aguirre, G. D. Optic nerve colobomas associated with unilateral focal serous retinal detachment in a dog - In-vivo imaging and outcome following laser retinopexy Veterinary Ophthalmology 24: 645-652, 2021.

Aguirre, G. D., Cideciyan, A. V., Dufour, V. L., Ripolles-Garcia, A., Sudharsan, R., Swider, M., Nikonov, R., Iwabe, S., Boye, S. L., Hauswirth, W. W., Jacobson, S. G., Beltran, W. A. Gene therapy reforms photoreceptor structure and restores vision in NPHP5-associated Leber congenital amaurosis Molecular Therapy 29: 2456-2468, 2021.

Song, C., Dufour, V. L., Cideciyan, A. V., Ye, G. J., Swider, M., Newmark, J. A., Timmers, A. M., Robinson, P. M., Knop, D. R., Chulay, J. D., Jacobson, S. G., Aguirre, G. D., Beltran, W. A., Shearman, M. S. Dose range finding studies with two RPGR transgenes in a canine model of X-Linked Retinitis Pigmentosa treated with subretinal gene therapy Human Gene Therapy 31: 743-755, 2020.

Iwabe, S., Dufour, V. L., Guzman, J. M., Holle, D. M., Cohen, J. A., Beltran, W. A., Aguirre, G. D. Focal/multifocal and geographic retinal dysplasia in the dog-In vivo retinal microanatomy analyses Veterinary Ophthalmology 23: 292-304, 2020.

Gardiner, K. L., Cideciyan, A. V., Swider, M., Dufour, V. L., Sumaroka, A., Komaromy, A. M., Hauswirth, W. W., Iwabe, S., Jacobson, S. G., Beltran, W. A., Aguirre, G. D. Long-term structural outcomes of late-stage RPE65 gene therapy Molecular Therapy 28: 266-278, 2020.

Dufour, V. L., Yu, Y., Pan, W., Ying, G. S., Aguirre, G. D., Beltran, W. A. In-vivo longitudinal changes in thickness of the postnatal canine retina Experimental Eye Research 192: 107926, 2020.

Dufour, V. L., Cideciyan, A. V., Ye, G. J., Song, C., Timmers, A., Habecker, P. L., Pan, W., Weinstein, N. M., Swider, M., Durham, A. C., Ying, G. S., Robinson, P. M., Jacobson, S. G., Knop, D. R., Chulay, J. D., Shearman, M. S., Aguirre, G. D., Beltran, W. A. Toxicity and efficacy evaluation of an adeno-associated virus vector expressing codon-optimized RPGR delivered by subretinal injection in a canine model of X-linked Retinitis Pigmentosa Human Gene Therapy 31: 253-267, 2020.

Guziewicz, K. E., McTish, E., Dufour, V. L., Zorych, K., Dhingra, A., Boesze-Battaglia, K., Aguirre, G. D. Underdeveloped RPE apical domain underlies lesion formation in canine bestrophinopathies Advances in Experimental Medicine and Biology 1074: 309-315, 2018.

Guziewicz, K. E., Cideciyan, A. V., Beltran, W. A., Komaromy, A. M., Dufour, V. L., Swider, M., Iwabe, S., Sumaroka, A., Kendrick, B. T., Ruthel, G., Chiodo, V. A., Heon, E., Hauswirth, W. W., Jacobson, S. G., Aguirre, G. D. BEST1 gene therapy corrects a diffuse retina-wide microdetachment modulated by light exposure Proceedings of the National Academy of Sciences of the United States of America 115: E2839-E2848, 2018.

Cideciyan, A. V., Sudharsan, R., Dufour, V. L., Massengill, M. T., Iwabe, S., Swider, M., Lisi, B., Sumaroka, A., Marinho, L. F., Appelbaum, T., Rossmiller, B., Hauswirth, W. W., Jacobson, S. G., Lewin, A. S., Aguirre, G. D., Beltran, W. A. Mutation-independent rhodopsin gene therapy by knockdown and replacement with a single AAV vector Proceedings of the National Academy of Sciences of the United States of America 115: E8547-E8556, 2018.

Beltran, W. A., Cideciyan, A. V., Boye, S. E., Ye, G. J., Iwabe, S., Dufour, V. L., Marinho, L. F., Swider, M., Kosyk, M. S., Sha, J., Boye, S. L., Peterson, J. J., Witherspoon, C. D., Alexander, J. J., Ying, G. S., Shearman, M. S., Chulay, J. D., Hauswirth, W. W., Gamlin, P. D., Jacobson, S. G., Aguirre, G. D. Optimization of retinal gene therapy for X-linked Retinitis Pigmentosa due to RPGR mutations Molecular Therapy 25: 1866-1880, 2017.

Downs, Louise M, Scott, Erin M, Cideciyan, Artur V, Iwabe, Simone, Dufour, Valerie, Gardiner, Kristin L, Genini, Sem, Marinho, Luis Felipe, Sumaroka, Alexander, Kosyk, Mychajlo S Overlap of abnormal photoreceptor development and progressive degeneration in Leber congenital amaurosis caused by NPHP5 mutation Human Molecular Genetics 25: 4211-4226, 2016.

Tofflemire, K. L., Whitley, E. M., Flinn, A. M., Dufour, V. L., Ben-Shlomo, G., Allbaugh, R. A., Griggs, A. N., Peterson, C. S., Whitley, D. R. Effect of topical ophthalmic dorzolamide(2%)-timolol(0.5%) solution and ointment on intraocular pressure in normal horses Veterinary Ophthalmology 18: 457-61, 2015.

DVM (Veterinary Medicine) University of Liege, School of Veterinary Medicine, Liege (Belgium), 2012

MSc (Veterinary Medicine) University of Liege, Liege, Belgium, 2013

University of Pennsylvania (2014 to 2020)
Post doctoral fellow in Comparative Ophthalmology

University of Pennsylvania (2020 to 2023)
Residency in Veterinary Ophthalmology