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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

Lab 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.  I am now generating a genetically engineered mouse overexpressing  mLST8 (mTOR associated protein, LST8 homolog) in retinal-pigmented epithelial (RPE) cells to understand the function of this protein in RPE 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 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.

Nadezda Stepicheva, PhD

Senior Research Scientist

Most people know me as Nadia, since my official name is long (it's even longer than written here). I started my scientific career as an MS student at Moscow State Academy of Fine Chemistry Technology in Russia where I worked on the lipid adaptation of bacteria to stress conditions. I continued my graduate training at the University of Arkansas, where I studied the role of lipids in vitiligo onset. I really loved lipid research, however, I felt that such a narrow and relatively rare expertise in lipids would not be enough to thrive in the field of molecular biology nowadays. To fill the gap in my training, I applied for a PhD program at the University of Delaware where I worked on the role of microRNAs in the development of sea urchin embryos. For my postdoctoral training, I wanted to move to a more clinically-relevant field and joined Debasish Sinha's Lab. My real passions are now cloning, teaching and scientific editing. In addition to working in the lab, I’m enjoying my life as a mom of a very cheerful boy and a pretty baby girl, who fill my heart with joy and pride. So, at the present moment my hobbies are limited to keeping my kids happy and entertained.


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’.


Haitao Liu, MD, PhD

Postdoctoral Associate

My name is Haitao, I came to the University of Pittsburgh as a postdoctoral associate after completing my PhD at Case Western Reserve University in 2019. I also earned my MD degree at Harbin Medical University (HMU) in China before I came to America as a research visiting scholar in 2012. I joined Dr. Sinha’s lab at the Department of Ophthalmology (University of Pittsburgh) as we have similar research interests on diabetic retinopathy (DR) and AMD. I am currently working on DR project, aiming to find out ways to stop or delay the onset of early development of DR. I love the research environment in the lab as we always discuss our project while sharing delicious food together. We are brothers and sisters here, and we always help each other. I also like the seminars that are held every Tuesday morning in the department as they bring scientists in the eye research field together and share their brilliant ideas and research findings. I am so excited to have such a good opportunity to work with these scientists and this is important for postdocs like me who want to excel in the eye research.

My favorite sport is usually basketball, but right now it is children’s slide and swing, same as my little girl's.

Haitao Liu p2.jpg

Anastasiia Strizhakova, DVM

Postdoctoral Associate

My name is Nastia, I'm from Russia. I have devoted most of my life to veterinary medicine after receiving a DVM degree at the Moscow State University of Applied Biotechnology. I started my professional career as a veterinarian, treating small pets. I am a practicing veterinarian with ten years of experience and an owner of a veterinary clinic in Moscow. I have professional skills in different areas of veterinary medicine such as ophthalmology, surgery, dermatology, dentistry, laboratory diagnostics, virology, endocrinology. However, over time, I realized that my true passion are the rules that govern the processes in the animal bodies, and I would like very much to do research work that goes beyond the simple treatment of animals. I am fortunate to join the Sinha Lab this year. AMD is highly prevalent in developed countries and ranks the third among the causes of blindness. It will be very interesting to dig into the molecular mechanisms underlying such an important disease that currently has no treatment available. 

My main hobby is Motorsport, I compete in several disciplines, and I am a multiple winner of competitions. I think it helps to develop such qualities as the ability to work in a team, become goal-oriented and to learn how to focus on that goal.


Olivia Chowdhury, MS

Visiting research student,

Department of Physiology, University of Calcutta, India

Like most bio-enthusiasts, my inclination toward biology began in high school. Good grades motivated me to take up Physiology after school. I graduated with a BS and MS degree in Human Physiology from the University of Calcutta, India. Soon after, I enrolled myself to a PhD program in the Department of Physiology of the same university. For my doctoral thesis, my research interest lies in exploring molecular mechanisms linking autophagy to inflammation and organ damage. I will be joining Sinha Lab as a visiting research student and study closely the pathogenesis of AMD. When I’m not running experiments, writing scientific articles or inventorying exhausted reagents, I enjoy teaching. I have been associated with a couple of undergraduate colleges in my city as Guest Faculty for several years. In addition, good food, good books and good company bring out the best in me. Watching movies, hanging out with friends and shopping are my go-to stress busters. Although I have not had enough opportunities so far, visiting new places is a thrill I want to experience.

Olivia Chowdhury (1).jpeg

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. 


Emma Mahally

Student Researcher

My name is Emma, and I am a sophomore undergraduate student at the University of Pittsburgh. I am majoring in Biological Sciences on the Pre-Med track, with a Spanish minor. I also am pursuing certificates in Global Health and Conceptual Foundations of Medicine. I’m excited to become more involved with research here in the lab. My hobbies include dancing (ballet, lyrical, jazz, tap), kayaking, and spending time with my cats. 


Mihir Nemani

Student Researcher

My name is Mihir Nemani, I am a Junior at the University of Pittsburgh, studying Biological Sciences and minoring in Chemistry and Theatre Arts. I am from Andhra Pradesh, India. Biology always fascinated me, with zoology and human anatomy and physiology always peaking my interest. Therefore, after my graduation I plan to continue studying biology again by getting into med school. At Dr. Sinha’s Lab, I am working on finding the effects of Trehalose on mTORC1 protein. I am really excited for the experience I am going to get from my peers and working here. In my free time, I love to read comic books, play football (soccer when I am in the US), write poems, and act.


Vishnu Maddipatla

Student Researcher

My name is Vishnu, originally from Northern Virginia, and I am an undergraduate student at the University of Pittsburgh studying Neuroscience and Economics. In the future, I am interested in attending medical school and eventually becoming a surgeon. At Dr. Debasish Sinha’s lab, I am excited to become more involved in hands-on RPE and AMD research and developing my lab skills. I hope to eventually pursue an independent, interdisciplinary research project through the lab by combining ophthalmology and neuroscience research. In my free time, I love reading, playing Spikeball, watching sports, and spending time with family and friends.



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 Medical Student at Chicago College of Osteopathic Medicine).

24.    Subrata Mishra, Ph.D., Senior Research Specialist, 4/2016-9/2017 (Currently a Scientist at the United States Pharmacopeia, Maryland).

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, PhD. Postdoctoral Associate, 01/2016-07/2021 (Currently Research Scientist at the Neural Stem Cell Institute in New York state)

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, PhD., 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)

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