Our Team
Principal Investigator
I studied Biology in Mainz, Germany, and got my Ph.D. in 1994 for work conducted at the Max-Planck Institute for Brain Research in Frankfurt/M. After a postdoc at The Rockefeller University (with A.J. Hudspeth), I became a faculty member at Harvard Medical School in 2000. My laboratory was part of the Eaton Peabody Laboratories at the Massachusetts Eye & Ear Infirmary.
In 2005, I moved to Stanford University, School of Medicine, Department of Otolaryngology — Head & Neck Surgery. I am a faculty member of the Institute for Stem Cell Biology and Regenerative Medicine at Stanford.
I am the first of my family to attend University. I try to help build a welcoming, fair, and supportive environment in which people from all backgrounds can thrive. I am not perfect, and I encourage my research team members to help me as we all need to set examples to make the world a better place.
I am no longer allowed (my lab told me! I break things) to touch a pipette and operate any of the expensive apparatus in my laboratory. This is ok - I like writing papers and to compete for funding. I am committed to helping my mentees succeed in any career they decide to pursue. I also rely on their feedback to help me on my journey. Science is fun and I have the job of my dreams!
Senior Instructor and
Scientific Co-Lead
I am a senior auditory scientist and Scientific Co-Lead in the Heller Laboratory, where I help shape the lab’s research direction and lead programs focused on inner ear regeneration and biological therapies for hearing loss.
My training spans pharmacology, cochlear pathophysiology, neurobiology, and regenerative medicine. After completing my Pharm.D. in Algeria and my M.Sc. and Ph.D. at the Institute for Neurosciences of Montpellier, I joined Stanford University in 2018 and became an Instructor in 2022.
My research investigates how birds naturally regenerate auditory hair cells after injury and how these mechanisms can be translated to the mammalian cochlea. By combining injury models, single-cell genomics, gene-regulatory analysis, and in vivo approaches, I aim to identify regenerative triggers that could ultimately support hearing restoration.
As Scientific Co-Lead, I mentor trainees, develop collaborations, and lead independent projects supported by competitive funding. I am committed to building a supportive scientific environment where rigorous research, mentorship, and team science can thrive.
Email:kafadar@stanford.edu
Where are you from? Constantine, Algeria
Education: Pharm.D. — University of Constantine; M.Sc. — University of Montpellier; Ph.D. — Institute for Neurosciences of Montpellier
Hobbies: Gardening, cooking for family and friends, hosting BBQs, and watching detective movies
I received my master’s degree in Molecular Cell Biology and Neurobiology at the University of Kaiserslautern in Germany and became fascinated by hearing science for my master's thesis and have been working in the broad field of hearing research ever since. During my master’s and doctoral theses, I had the opportunity to explore different aspects of sound processing in the auditory brainstem. Currently, I have shifted my research focus from the auditory brainstem to the auditory periphery. In April 2022, I started my postdoctoral position in the lab of Prof. Stefan Heller at Stanford University to study hair cell regeneration in the mouse cochlea. My biggest dream is to gain a broad knowledge and understanding of the breadth of the auditory system and to gain a more in-depth understanding of each aspect from the periphery to central processing. I believe that a holistic knowledge of auditory processing is essential for groundbreaking research and that it will broaden the possible directions for my future career and specialization as an independent scientist.
Email: aysems@stanford.edu
Where are you from? Ludwigshafen am Rhein, Germany
Education: Ph.D. (Kaiserslautern, Germany)
Hobbies: Biking, baking, reading fantasy books, playing board games, skydiving, hiking, traveling
Hello! I was born and raised in sunny SoCal. I attended Claremont McKenna College and then moved across the country to Bethesda, Maryland to pursue a postbaccalaureate fellowship at the National Institute on Deafness and Other Communication Disorders. During my time there, I spent a great deal learning about the fascinating process of inner ear development in the lab of Dr. Doris Wu. I then came back to the West Coast in the fall of 2022 and started my journey as a PhD student in the Stem Cell Biology & Regenerative Medicine graduate program. The inner ear is an intricate organ and there are still many open questions. As a bilateral cochlear implant wearer, I hope to contribute to a better understanding of inner ear biology, which will drive the development of therapeutics to treat hearing and balance disorders.
Email: ahuang97@stanford.edu
Where are you from? Diamond Bar & Newport Beach, California
Education: Claremont McKenna College (BA, Molecular Biology, 2019)
Hobbies: Cooking, painting, videogames, swimming
I grew up in a small town in southern India and moved to Bangalore, India, for undergraduate education, where I received a Bachelor of Engineering in Biotechnology. Driven by my curiosity and enthusiasm to perform scientific research, I moved to Edmonton, Canada, where I received an MSc in Experimental Oncology from the University of Alberta. After that, I briefly worked as a research technologist in an NGS core facility and then as a lab manager and research tech at the University of Alberta.
I did my PhD with Dr. Andrew Groves in the Genetics and Genomics program at Baylor College of Medicine. This was my first foray into the world of developmental biology, and I was hooked. During my PhD, I worked on understanding the role of BMP signaling in the cell fate determination and patterning of the organ of Corti, the sensory tissue that houses the hair and supporting cells which are crucial to hearing function. I joined Dr. Heller’s lab in July 2024, and I am excited to take a deep dive into the field of cellular reprogramming and regeneration in the inner ear.
Email: ishwarvh@stanford.edu
Where are you from: Gulbarga, Karnataka, India
Education: MSc. (University of Alberta, Canada), PhD (Baylor College of Medicine, USA)
Hobbies: Tinkering with electronics and setting up a home lab, reading and watching science fiction, cooking, and playing guitar, badly!
I grew up in Shanghai, China, and came to the U.S. for my undergraduate education in 2017. I studied biology at Grinnell College in Grinnell, IA, and moved to New York City after graduation for a research position in the Choi lab at Columbia University. I spent two years in the Choi lab studying the activation mechanism of the insulin receptor and an insulin mimetic peptide. While training at the Choi lab, I realized my research interest in regenerative medicine and became more determined to pursue a PhD. In September 2023, I moved to the Bay Area for the first time to start my journey as a PhD student in the Stem Cell Biology and Regenerative Medicine program at Stanford. I am excited to explore the field of stem cells and regenerative medicine and spend the next five years or so on the sunny West Coast.
Email: wujiayi@stanford.edu
Where are you from? Shanghai, China
Education: Grinnell College, IA (BA, Biology)
Hobbies: Watching dramas, traveling, playing with my cat
I was born and raised in Boston, Massachusetts. In 2019, I began my undergraduate studies in biology and anthropology at Bowdoin College in Brunswick, Maine, where I graduated with Honors. During my time at Bowdoin, I worked in the Horch lab studying the regeneration of the auditory system in crickets after injury which kickstarted my interest in regenerative medicine. As an undergrad, I had the opportunity to work in the Greenwald lab at Columbia University and the Updike lab at MDIBL, which encouraged me to pursue a PhD. In the fall of 2023, I began my journey as a PhD student in the Stem Cell Biology and Regenerative Medicine graduate program at Stanford University. I am excited to refine my interest in regenerative medicine and learn more about the field of stem cell biology during my time in the Bay Area.
Email: lmirandp@stanford.edu
Where are you from? Boston, Massachusetts
Education: Bowdoin College (BA, Biology, Minor in Anthropology, 2023)
Hobbies: Teaching my cat tricks, hiking, and baking
Hui Zhang
I was born and raised in Shanxi, China. In 2015, I moved to Nanjing to begin my university studies, where I received my B.S. in Biomedical Engineering in 2019 and completed my Ph.D. in Biology in 2024. During my Ph.D., I worked on bioengineered tissue regeneration platforms and drug delivery systems. In particular, I became fascinated by hearing research and contributed to projects involving progenitor cell-derived organoids, inner ear drug delivery systems, and gene therapy. This experience sparked a strong interest in organoid-based approaches and gene therapy for hearing restoration, which I am eager to further explore. In April 2026, I joined Dr. Stefan Heller’s lab, where I focus on otic organoid development. I am excited to explore organoids as powerful models for studying development and regenerative medicine in a collaborative environment.
Email: huizhang26@stanford.edu
Where are you from? Shanxi, China
Education: B.S. Biomedical Engineering (Southeast University); Ph.D. Biology (Southeast University)
Hobbies: Jogging, enjoying ball sports, chips and ice cream!
I grew up in Nanjing, a famous historical city in China. In 2014, I began my undergraduate education at Anhui Agricultural University in Hefei, China, where I obtained a Bachelor’s degree in Biological Sciences. Later, in 2018, I received the postgraduate recommendation to Southeast University in Nanjing, China, where I studied under Dr. Rengjie Chai, focusing on auditory research through bioinformatics strategies. In 2020, I joined Dr. Yan Zhang's lab at Zhejiang University in Hangzhou, China, engaging in a collaborative project on the structural mechanisms of auditory proteins. After earning my Ph.D. in Biology, I realized my deep interest in auditory research, particularly in the area of hair cell regeneration. In March 2025, I was thrilled to join Dr. Stefan Heller's lab, embarking on a new journey in the hopes of making significant contributions to the field of hair cell regeneration.
Email: xiangyum@stanford.edu
Where are you from: Nanjing, China
Education: B.S. (Anhui Agriculture University, China), Ph.D. (Southeast University, China)
Hobbies: Biking, photography, and traveling