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Debasish Sinha, PhD

Jennifer Salvitti Davis, M.D. Chair in Ophthalmology

Professor of Ophthalmology, Cell Biology and Developmental Biology

Adjunct faculty, Ophthalmology, The Johns Hopkins University School of Medicine and Department of Environmental Health & Engineering, The Johns Hopkins Bloomberg School of Public Health

Visiting Faculty, Narayana Nethralaya Foundation, Bengaluru, India.

For the past several years, I have been trying to understand the role of lysosomes in retinal pigment epithelial (RPE) cells under normal health and disease conditions.  I have generated several genetically engineered mice as tools to understand such functions.  My major interest is to understand the mechanisms by which mechanistic target of rapamycin complex 1 (mTORC1), a known negative regulator of autophagy, is recruited and how the signaling pathway proteins are assembled on the lysosomes of the RPE. Due to its pivotal and versatile governance of cellular well being, mTORC1 has been the focus of intensive study as a therapeutic target in age-related diseases. However, its broad influence on multiple critical cellular processes is also the root cause of considerable side effects when directly targeted by rapamycin or new generation rapalogs. We have identified unique proteins that rejuvenate lysosomal function of the RPE that could circumvent the side effects that result from directly targeting mTORC1 and to develop therapeutic target in age-related macular degeneration (AMD) disease. AMD is the leading cause of blindness among the elderly, and a significant public health problem.  Our studies have clinical significance since they can provide a novel target for the development of therapeutic strategies to delay the development of pathologies seen in early AMD.  When I am not doing research, I like to travel and meet people of different cultures around the world.  My hobbies are boating and biking and I enjoy watching sports with my son.


Stacey Hose, BA

Laboratory Manager

My name is Stacey and I am the Laboratory Manager for the Sinha Lab.  I joined Debasish Sinha at Johns Hopkins after completing my degree in biology from Western Maryland College, a small liberal arts school that has since been renamed McDaniel College. Over the years, I have been involved in several projects and published papers as a first/co-author as the lab works to decipher the role of retinal-pigmented epithelial (RPE) cells in health and disease​.  In addition to my research, I also manage the day-to-day operations of the lab, which includes ordering (reagents, supplies and animals), maintaining all necessary protocols, final preparation and submission of manuscripts to journals, preparation and managing federal, foundation and industry grants, and handling laboratory personnel needs.  I manage the yearly budget and am the liaison for our many national and international collaborations. When I am not hard at work in the lab, my hobbies include photography, reading, and skiing. 


J. Samuel Zigler, Jr., PhD

Senior Investigator

My career in Biology started at Bridgewater College in Virginia where I earned a BA in Biology before moving on to Duke University for graduate studies in the Department of Zoology. During my PhD work there, I serendipitously was introduced to the biology of the ocular lens and its major component proteins, the crystallins. After completing dissertation studies on comparative aspects of β- crystallin from a variety of vertebrate species, I moved to the Intramural Research Program of the National Eye Institute, NIH. For the next 30 years, I was part of the Lens Research Group there, studying various aspects of lens biology and cataractogenesis with primary interest in the structure and function of crystallins.
In 2007 I was invited to join Debasish Sinha's group at the Wilmer Eye Institute, Johns Hopkins School of Medicine to continue collaborative studies on two spontaneous rat mutations. While there, I was able to pursue my interest in crystallins by studying the functions of βA3/A1-crystallin in ocular tissues other than the lens and was also involved in identifying the gene mutation responsible for the frogleg mutation. Since the Sinha Lab re-located to Pittsburgh, I am in the lab only infrequently, but serve as a sounding board and advisor as needed and also help with writing and editing manuscripts and grant proposals.

Sayan Ghosh, PhD

Postdoctoral Associate

I am a post-doctoral associate in the Sinha Lab. I am originally from India and I did my Ph.D from University of Calcutta, Kolkata, India in Neuroscience. I am an immunologist by training and I am currently working to unravel the molecular mechanisms associated with inflammatory transitions during the progression of age-related macular degeneration (AMD). I was awarded the Fulbright fellowship for doctoral research-2015, and I did a portion of my PhD work in the Debasish Sinha's lab. I love science, performing new experiments and trying to know the unknown gives me the push to do better science every day. Apart from the research, I love to travel, meet new people, spend time with my friends and I am a complete foodie (I eat anything and everything-well mostly). One of my favorite past time is cooking and I tend to experiment with it a lot too, well luckily most of the time the food-related experiments turn out well, as any statistician would say, ‘statistically significant positive outcome’.


Sridhar Bammidi, PhD

Postdoctoral Associate

I hail from Hyderabad, India. A seeker at heart and a learner for life. I pursued my PhD in Ocular Neuroscience, from PGIMER, Chandigarh and have been working on the retina and eye for the past 12 years. My interests primarily focus towards understanding retinal degeneration (I have worked both on glaucoma and AMD), understanding the autonomic cues behind them and trying to explore any underlying endogenous regenerative mechanisms which can be therapeutic for the disease. I am a developmental/regenerative/translational biology Philomath and believe that every degenerative disease has a cue for understanding its therapy or reversal in our body. The unknowns of the living body and its physiology thrills and motivates me to explore further. 
Beyond science and research, I love cooking; it’s meditation for me.
I am a very social person by nature and love to cook, feed and host friends. I am the ‘Monica Geller’ for my friends. I love to travel, learn new languages, meet people and explore cultures. I have immense interest in classical art forms. Anthropology of world religions attracts me a lot. The great diversity in our forms of social existence across the world and through time, simply amazes me.

Sridhar pic.jpg

Victoria Koontz, BS

Research Technician

My interest in science began when I realized I enjoyed chemistry. From there the floodgates to the world of science opened and I knew it was a path I would enjoy following. I went on to obtain a Bachelor of Science degree majoring in Biological Sciences with a concentration in Organismal Biology and a minor in Chemistry. Graduating summa cum laude from Point Park University in December of 2020. I've explored many different settings of science and medicine. Working in a nursing home, pharmacy, and volunteering in a hospital. Now my journey continues exploring it in a research setting. I'm looking forward to growing my skills and knowledge in the Sinha Lab. In school my favorite class was genetics and I'm looking forward to using it in my work. My future plans are to go to medical school. However, right now I'm focusing on my health, happiness, and living my life to the fullest. My hobbies include spending time with my sister's cats, crossword puzzles, supporting cultural arts, eating out, playing piano, and most importantly making those I love around me feel cared for and special. 


Pooja Gautam, MS

Visiting Health Sciences Research Fellow

I am Pooja Gautam, a PhD scholar at BITS-Pilani, K K Birla Goa campus, India. Recently, I joined the Sinha Lab as a visiting graduate scholar. Prior to this, I completed my Master's degree in neuroscience and gained research experience at prestigious institutions such as NIMHANS and CSIR-CCMB. I have a strong passion for research, and I am thrilled to have the opportunity to work in the Sinha Lab and expand my knowledge. I enjoy exploring the city and experimenting with cooking during my free time.

Mihir Nemani

Visiting Health Sciences Research Fellow

The world of Animal Planet started my interest in Biology. I used to spend hours watching T.V. listening to the narration of Sir David Attenborough explaining how the intricate nature around us functioned. Since then, I decided to pursue a career in biology. I recently graduated from the University of Pittsburgh with a degree in Biological Sciences, with a minor in Chemistry and Theatre Arts (because I also like to be a little dramatic). I’ve always liked the field of medicine, so I’ve tried to gain as much insight possible about the field. I have volunteered in various departments in hospitals (including mail delivery), shadowed different nurses, and gained some vital laboratory experience. I look forward to working in the Sinha Lab, as the field of ophthalmology has had my interest since a young age because of its close relation to me and my family, and I know that working here will provide me the vital knowledge and experience that I will need. On the more fun and interesting side of my life, my hobbies include playing football (not the American one), reading graphic novels, photography, and writing poems.

Shruti Dhar

Student Researcher

I am a junior at the University of Pittsburgh and am majoring in Biological Sciences on the Pre- Med track with a minor in Chemistry and Gender, Sexuality and Woman's Studies (GSWS) and certification in Conceptual Foundations of Medicine. I have always been interested in the field of medicine with a huge penchant towards research. Outside of research lab, I have also volunteered at UPMC hospitals. My hobbies include writing poems, swimming, exploring the city with my friends and hiking. 


1.    Cheng Zhang, M.D. Postdoctoral Fellow, 6/2008-8/2010 (Currently he is an Assistant Professor, Department of Ophthalmology, Albert Einstein College of Medicine of Yeshiva University, New York).

2.    Geetha Parthasarathy, Ph.D. Postdoctoral Fellow, 6/2009-8/2010, (Currently a Junior faculty, Tulane National Primate Research Center, LA)

3.    Gitanjali Sehrawat, Ph.D. Postdoctoral Fellow, 01/2009-1/2010 (Currently a Clinical Scientist at Merck/ExecuPharm)

4.    Tanusree Sen, Ph.D. Postdoctoral Fellow, 1/2011-6/2012 (Currently a Research Assistant Professor at University of Pittsburgh)

5.    Mallika Valapala, Ph.D. Postdoctoral Fellow, 2/2011-5/2015 (Currently an Assistant Professor, Indiana University School of Optometry).

6.    Andrew Klise, M.D. Research Student, 4/2005-6/2010 (Practicing Physician at Actify Neurotherapies, North Carolina). 

7.    Bonnie Patek, D.O. Laboratory Technician, 3/2009-6/2010 (Practicing Physician, Internal Medicine and General Gastroenterology, Pennsylvania).

8.    Bo Ma, M.D. /Ph.D. student, 2009-2010 (Currently an Assistant Professor at Shanghai Jiao Tong University and the 9th hospital in Shanghai, China).

9.    Souvonik Adhya, Laboratory Technician, 5/2010-8/2011 (Medical Resident in Arkansas).

10.    Celine Gongora, Ph.D. Visiting Scientist, 06/2010 (Lead Scientist at IRCM, INSERM086, Montpellier, France).

11.    Bhaja K. Padhi, Ph.D. Visiting Scientist, 4/2011-9/2011 (Scientist at Health Canada, Ottawa, Canada).

12.    Vaishnavi Sridhar, Volunteer, 6/2010-8/2010, (Undergraduate student, UMBC, Maryland).

13.    Annum Shaikh, MPH., Research Technician, 6/2010-8/2010 (Currently an Epidemiologist with the Virginia Department of Health),

14.    Fang Yang, Research Specialist, 1/2011-2/2012 (Research Specialist, JHMI)

15.    Marisol Cano, Ph.D. Postdoctoral Fellow, (Currently a Research Associate, Junior Faculty, at the Wilmer Eye Institute). 

16.    Vlad Damian, D.D.S., Research Technician, 4/2011-8/2011 (Practicing Dentist in Pennsylvania).

17.    Bidesh Ghosh, Summer Student, 6/2011-8/2011 (United States Food & Drug Administration).

18.    Piyush Padhi, Summer Student, 6/2011-8/2011, (Currently a Ph.D. student at Iowa State University).

19.    Limin Gu, M.D. /Ph.D. student, 3/2012-6/2012, (Ophthalmologist, Shanghai, China).

20.    Samhita Sengupta, Volunteer, 1/2013-8/2013 (Undergraduate student at University of Maryland).

21.    Xi Peng, Ph.D. Student, 2/2015-1/2016 (Graduate student, Dr. Jeremy Nathan’s laboratory, The Johns Hopkins University School of Medicine).

22.    Gregory Konar, Undergraduate Researcher & Woodrow Wilson Fellow, 8/2015-9/2017 (Ph.D. Student at Vanderbilt University).

23.    Tianqi Luo, B.S., Laboratory Technician, 2/2016-2/2017 (Currently a Practicing Physician in Nebraska).

24.    Subrata Mishra, Ph.D., Senior Research Specialist, 4/2016-9/2017 (Currently a Principal Investigator at the Institute for Bioscience & Biotechnology Research, University of Maryland, NIST).

25.    Khushbhu Agrawal, Ph.D. Visiting Exchange Student, 12/2016-4/2017 (Currently a Scientist at Palacky University, Czech Republic).

26.    Arupratan Das, Ph.D., K99 Mentee, 9/2017-Present (Assistant Professor, Department of Ophthalmology, Indiana University).

27. Imran Bhutto, M.D/Ph.D. Research Assistant Professor, 10/2017-02/2019 (Currently Experimental Pathologist, Wilmer Eye Institute, Johns Hopkins School of Medicine) 

28. Joseph Weiss, BA. Research Technician, 09/2018 - 04/2020 (Currently Medical Student at Geisinger Medical School).

29. Meysam Yazdankhah, Ph.D. Postdoctoral Associate, 01/2016-07/2021.

30. Urvi Gupta, Research Trainee, 05/2020-05/2021 (Currently Medical Student at Case Western Reserve University)
31. Chris Fitting, BS., Research Technician, 08/2019-06/2021 (Currently trail crew member with the Allegheny County parks department).

32. Peng Shang, Ph.D., Visiting Research Student -> Postdoctoral Associate, 09/2014-06/2022 (Currently Research Scientist at Doheny Eye Institute).

33. Rachel Daley, Research Technician, 10/2021-06/2022 (Currently Medical Student at Edward Via College of Osteopathic Medicine).

34. Nadezda Stepicheva, Ph.D., Postdoctoral Fellow, 1/2017-12/2022 (Currently a Research Scientist, Department of Neurology, University of Pittsburgh).

35. Olivia Chowdhury, B.S., M.S., Academic Health Sciences Research Fellow, 10/2020-12/2022 (Currently a graduate student, University of Calcutta).

36. Haitao Liu, M.D., Ph.D., Postdoctoral Associate, 5/2019-1/2023 (Currently a Postdoctoral Associate, Department of Ophthalmology, University of Pittsburgh).

37. Vishnu Maddipatla, B.S., Undergraduate Student Worker, 9/2021-4/2023 (2023 Graduate of University of Pittsburgh).

38. Anastasia Strizhakova, D.V.M., Postdoctoral Associate, 10/2020-6/2023.

39. Emma Mahally, B.S., Undergraduate Student Worker, 9/2021-12/2023 (2023 Graduate of University of Pittsburgh).

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