Dr. Billie Beckwith-Cohen


billie

Background: I was born and raised in Tel-Aviv, Israel, and spent my summers with my family in Manhattan, NY. I earned a BSc in Life and Medical sciences from Tel-Aviv University in Israel, and a Doctor of Veterinary Medicine from the Hebrew University of Jerusalem. After completing my veterinary education, I worked in small animal private practice, and simultaneously obtained an MBA at Tel-Aviv University. My ongoing passion for vision and ophthalmology lead me to fellowship training in comparative ocular pathology at UW-Madison, WI, and then to pursue a PhD at the department of Vision Science at UC Berkeley.

 Current Research: At the Kramer lab my work has been focused on two main fields.

1.     Optical sensing of neuronal activity in a cone-rich retina- Lateral inhibition is a key neural network phenomenon that enhances contrast sensitivity in sensory systems. The reciprocal synapse between cone photoreceptors and horizontal cells underlies lateral inhibition. Despite being recognized in the early 1950s, the signal, which mediates it, is still actively debated. My work at UC Berkeley includes research aimed at advancing our understanding of retinal physiology and circuitry using transgenic zebrafish models. This work includes projects, which support the theory by which lateral inhibition is mediated by a proton signal. I have been examining the proton gradient within the cone to horizontal cell synaptic cleft using three lines of transgenic zebrafish, which express genetically encoded fluorescent pH probes, two of which were developed in the laboratory. I have been using 2-photon Calcium imaging and immunohistochemistry coupled with super-resolution imaging techniques to help localize these probes within the synaptic cleft. Furthermore, I have been performing electroretinograms on transgenic zebrafish larvae and 2 -photon Calcium imaging on ex-vivo retinae, expressing designer receptors exclusively activated by designer drugs (DREADDs) and Pharmacologically Selective Actuator Modules (PSAMs), as well as genetically encoded Calcium indicators (the GECI GCaMP6f) to examine how pharmacological manipulation of horizontal cells affects the ERG as a whole, and more specifically retinal ganglion cell activity during lateral inhibition.

Beckwith-Cohen B, Holzhausen L, Kramer R. Optogenetic detection of spatial inhomogeneity of protons in the synaptic cleft during horizontal cell to cone feedback underlying lateral inhibition. Investigative Ophthalmology & Visual Science. 58(8):2977-2977.

2. Applying photoswitch compounds to impart visual sensitivity to degenerated retinae and to investigate retinal function following retinal degeneration. Retinal degeneration in retinitis pigmentosa (RP) severely affects the outer retina, while leaving much of the inner retinal circuitry intact. Currently, I am working on the optimization of formulations to allow for long lasting effects of photoswitches injected intravitreally into murine and rat models of RP. In order to study the effects of photoswitches on retinal physiology and remodeling I am utilizing behavioral assays, and intend to incorporate Calcium imaging to study the physiological effects that photoswitches have on specific retinal ganglion cells. The lab employs 2-photon microscopy for Calcium imaging for both ex-vivo and soon to be performed in-vivo retinal imaging.

Prior Publications:

B. Beckwith-Cohen, L.B.C Teixeira, D.J Maggs, R.R. Dubielzig, Feline Epitheliotropic Mastocytic Conjunctivitis. Veterinary Pathology, 2017 Jan;54(1):141-146. Epub Jun 2016.

B. Beckwith-Cohen, E. Bentley, D.J. Gasper, G. McLellan, R.R. Dubielzig, Immune-Mediated Keratitis in Dogs Following Treatment with Carbonic-Anhydrase Inhibitors. Journal of the American Veterinary Medical Association, 2015 Dec;247(12):1419-1426.

B. Beckwith-Cohen, D.J. Gasper, E. Bentley, H. Gittelman, A.E. Ellis, K.F. Snowden, B.C. Shock, M.J. Yabsley, R.R. Dubielzig, Protozoal Infections of the Cornea and Conjunctiva in Dogs Associated with Chronic Ocular Disease and Topical Immunosuppression. Veterinary Ophthalmology, 2016 May 3;19(3):206-213. Epub Jun 2015.

B. Beckwith-Cohen, L.B.C Teixeira, J.A. Ramos-Vara, R.R. Dubielzig, Squamous Papillomas of the Conjunctiva in Dogs: A Condition Not Associated With Papillomavirus Infection. Veterinary Pathology, 2015 Jul;52(4):676-680. Epub Oct 2014.

B. Beckwith-Cohen, E. Bentley, R.R. Dubielzig, The Outcome of Iridociliary Epithelial Tumor Biopsies in Dogs, A Retrospective Study. Veterinary Record, 2015: 176(6) 147. Epub Oct 2014.

B. Beckwith-Cohen, L.B.C Teixeira, R.R. Dubielzig, Presumed Primary Intraocular Chondrosarcoma in Cats. Journal of Veterinary Diagnostic Investigation, 2014: 26(5) 664-668.

B. Beckwith-Cohen, D. Elad, T. Bdolah-Abram, R. Ofri, Comparison of Tear pH in Dogs, Horses and Cattle. American Journal of Veterinary Research, 2014: 75(5): 494-499.

B. Beckwith-Cohen, I.H. Horowitz, T. Bdolah-Abram, A. Lublin, R. Ofri, Differences in Ocular Parameters Between Diurnal and Nocturnal Raptors. Veterinary Ophthalmology, 2015: Suppl s1:98-105. Epub Nov 2013.

B. Beckwith-Cohen, O. Koren, S. Blum, D. Elad, Variations in Vaginal pH in Dairy Cattle Associated with Parity and the Periparturient Period, Israel Journal of Veterinary Medicine, 2012: 67(1): 55-59.