Leigh Turner, Ph.D.

Leigh Turner, Ph.D.

Professor and Director, UCI Center for Health Ethics

Biography

Leigh Turner is a Professor in the School of Population & Public Health’s Department of Health, Society, and Behavior and Director of UCI’s Center for Health Ethics. Turner is a member of the Sue & Bill Gross Stem Cell Research Center and UCI MIND.

Turner’s primary research program addresses ethical, legal, and social issues related to stem cells and regenerative medicine. In particular, Turner and his research team use methods and theories from bioethics and the social sciences to analyze the marketing representations, clinical activities, and commercial practices of businesses engaged in direct-to-consumer advertising of stem cell interventions, exosomes, and other purported regenerative medicine products.

Current Research

In the United States, more than one thousand businesses sell putative “stem cell treatments” and “exosome therapies” that have not been approved by the U.S. Food & Drug Administration and at present are unsupported by convincing scientific evidence of safety and efficacy. Businesses market such “treatments” for ALS, Alzheimer’s disease, autism spectrum disorder, cerebral palsy, chronic obstructive pulmonary disease, multiple sclerosis, muscular dystrophy, Parkinson’s disease, osteoarthritis, spinal cord injuries, sports-related musculoskeletal injuries, and many other diseases and injuries. Some patients have suffered serious injuries after being administered such unproven and unapproved products. Other patients have experienced significant financial losses after being deceived by deceptive marketing claims.

In addition to posing risk of physical injuries and financial harms to individual patients, many businesses selling unproven stem cell interventions or exosome products engage in activities with harmful collective consequences. For examples, some businesses circulate health-related misinformation on company websites and social media platforms, make inaccurate claims about the Food and Drug Administration and other regulators, blur important distinctions between treatment and research, divert individuals from opportunities to participate in well-designed and carefully conducted clinical trials, or claim to prevent or treat COVID-19 by selling supposedly “immune-boosting” stem cell products that have not been rigorously tested in controlled clinical trials. Such practices can cause collective harms such as promoting public misunderstanding of stem cells and stem cell therapies and diverting patients away from facilities where they might have an opportunity to participate as research subjects in well-designed and carefully conducted controlled clinical trials. Turner’s research considers both individual and collective implications of premature commercialization of purported stem cell interventions, exosome products, and other putative regenerative medicine therapies.

Turner’s current research examining the U.S. direct-to-consumer marketplace for purported stem cell treatments is supported by the California Institute for Regenerative Medicine. He has previously received funding for this work from the Pew Charitable Trusts and UCI’s Newkirk Center for Science and Society.

Developing Research Initiative

In addition to his primary research focus, Turner is involved in an emerging research initiative that integrates research in biomedical engineering, neurology, engineering, and neurosurgery with bioethics scholarship. This multi-year research project is investigating whether it is possible to integrate stem cell research with engineering principles and restore motor functions in patients who have suffered brain damage from strokes or suffered other serious neurological injuries. Funded by the National Science Foundation, Turner is part of a UCI research team that includes Dr. An Do, Dr. Hung Co, Dr. Zoran Nenadic, and USC neurosurgeon Dr. Charles Liu. Turner is leading the team’s exploration of ethical, legal, and social issues related to this research initiative.

Additional Areas of Research

Turner has also published on such topics as the ethics of self-funded or “pay-to-participate” clinical studies, ethical issues related to online crowdfunding for medical care, the ethics of non-trial expanded access to investigational stem cell-based interventions, “right-to-try” legislation and access to unapproved medical products, ethical and social dimensions of health-related travel, ethical issues in end-of-life care, case-based reasoning in bioethics, and bioethics in multicultural, multiethnic, multifaith societies.

In addition to publishing articles on a variety of topics, Turner is a co-editor of Risks and Challenges in Medical Tourism: Understanding the Global Market for Health Services and The View from Here: Bioethics and the Social Sciences.

Prior Appointments

Before joining UCI’s faculty in 2021, Turner was an Associate Professor at the University of Minnesota Center for Bioethics and School of Public Health. Prior to his time in Minneapolis, Turner was an Associate Professor and William Dawson Scholar at McGill University’s Biomedical Ethics Unit and Department of Social Studies of Medicine. Before taking an academic position at McGill, Turner was a Clinical Assistant Professor at the University of Toronto Joint Centre for Bioethics and a clinical ethicist at Baycrest Centre for Geriatric Care and Sunnybrook Health Sciences Centre. After completing his doctoral degree in Religion & Social Ethics at the University of Southern California, Turner began his career as a Research Associate at the Hastings Center.

Visiting Fellowships

Turner has been a Visiting Fellow at the Brocher Foundation in Hermance, Switzerland; Erasmus Mundus Visiting Scholar, Radboud University Nijmegen, the Netherlands; Distinguished Visiting Fellow, Comparative Program on Health and Society, University of Toronto Munk School of Global Affairs, Toronto, Ontario, Canada; Member, School of Social Science, Institute for Advanced Study, Princeton, New Jersey, USA; National Endowment for the Humanities/Sealy & Smith Foundation Visiting Scholar, University of Texas Medical Branch Institute for the Medical Humanities, Galveston, Texas; and Ryan Bioethicist in Residence, Southern Illinois University, Carbondale, Illinois, USA.

Selected Publications Addressing Ethical, Legal, and Social Issues Related to Stem Cell Research and Regenerative Medicine

Trinh A, Turner L. 2025. Challenging Reward Structures and Organizational Cultures That Propagate Stem Cell Hyperbole. Stem Cell Reviews and Reports 21, 8: 2810-2819.

Prange S, Turner L. 2025. LGBTQ+ persons, queer bioethics, and inclusivity in stem cell research and regenerative medicine. Regenerative Medicine 20, 9: 387-397.

Jonlin E, Fujita M, Isasi R, Kato K, Munsie M, Muto K, Niakan K, Saha K, Sugarman J, Turner L, Hyun I. 2025. What Does ‘Appropriate Scientific Justification’ Mean for the Review of Human Pluripotent Stem Cell, Embryo, and Related Research? Stem Cell Reports 20, 5: 1-9.

Ikonomou L, Munsie M, Power C, Sipp D, Turner L, Rasko J. 2024. Effective Regulatory Responses to Predatory Stem Cell Markets in Australia and Canada. Cell Stem Cell 31, 10: 1393-1397.

Turner L, Wang J, Martinez Jr J, Najjar S, Rajapaksha Arachchilage T, Sahrai V. 2024. U.S. Businesses Engaged in Direct-to-Consumer Marketing of Perinatal Stem Cell Interventions Following the FDA’s Enforcement Discretion Era. Cytotherapy 26, 4: 393-403.

Turner L, Martinez Jr. J, Najjar S, Rajapaksha Arachchilage T, Sahrai V, Wang, J. 2023. Regulatory Claims Made by U.S. Businesses Engaged in Direct-to-Consumer marketing of Purported Stem Cell Treatments and Exosome Therapies. Regenerative Medicine 18, 11: 857-868.

Turner L, Martinez Jr. J, Najjar S, Rajapaksha Arachchilage T, Wang, J. 2023. Businesses Marketing Purported Stem Cell Treatments and Exosome Therapies for COVID-19: An Analysis of Direct-to-Consumer Online Advertising Claims. Stem Cell Reports 18, 11: 2010-2015.

Turner L, Martinez Jr. J, Najjar S, Rajapaksha Arachchilage T, Sahrai V, Wang J. 2023. Safety and Efficacy Claims Made by U.S. Businesses Marketing Purported Stem Cell Treatments and Exosome Therapies. Regenerative Medicine 18, 10: 781-793.

Ikonomou L, Cuende N, Forte M, Grilley B, Levine A, Munsie M, Rasko J, Turner L, Bidkhori H, Ciccocioppo R, Grignon F, Srivastava A, Weiss D, Zettler P, Levine B. 2023. International Society for Cell & Gene Therapy Position Paper: Key considerations to support evidence-based cell and gene therapies and oppose marketing of unproven products. Cytotherapy 25, 9: 920-929.

Zettler P, Ikonomou L, Levine A, Turner L, Grilley B, Roxland B. 2023. An International Society for Cell & Gene Therapy working group short report on the future of expanded access to unapproved cell and gene therapies. Cytotherapy 25, 7: 712-717.

Ikonomou L, Magnusson M, Dries R, Herzog E, Hynds R, Borok Z, Park J-A, Skolasinski S, Burgess J, Turner L, Mojarad S, Mahoney J, Lynch T, Lehmann M, Thannickal V, Hook J, Vaughan A, Hoffman E, Weiss D, Ryan A. 2022. Stem cells, cell therapies, and bioengineering in lung biology and disease 2021. American Journal of Physiology-Lung, Cellular, and Molecular Physiology 323: L341-L354.

Akkas F, Turner L, Richardson E. 2022. Adverse events related to unapproved stem cell
products and other regenerative interventions-recommendations for more robust regulation
of the direct-to-consumer marketplace. Regenerative Medicine 2022; 17, 2: 63-68.

Turner L. 2022. Hope, hype, cures, and persons with cerebral palsy. Developmental Medicine and Child Neurology 64, 1: 8.

Turner L, Munsie M, Levine A, Ikonomou L. 2021. Ethical Issues and Public Communication in the Development of Cell-based Treatments for COVID-19: Lessons from the Pandemic. Stem Cell Reports 16, 11: 2567-2576.

Turner L. 2021. The American stem cell sell in 2021: U.S. businesses selling unlicensed and unproven stem cell interventions. Cell Stem Cell 28, 11: 1891-1895.

Turner L., Snyder J. 2021. Ethical issues concerning a pay-to-participate stem cell study. Stem Cells Translational Medicine 10: 815-819.

Turner L. 2021 ISSCR’s Guidelines for Stem Cell Research and Clinical Translation: Supporting development of safe and efficacious stem cell-based interventions. Stem Cell Reports 16: 1394-1397.

Lovell-Badge R., Anthony A., Barker R., Bubela T., Brivanlou A., Carpenter M., Charo, A., Clark A., Clayton E., Cong Y., Daley G., Fu J., Fujita M., Greenfield A., Goldman S., Hill L., Hyun I., Isasi R., Kahn J., Kato K., Kim, J-S., Kimmelman J., Knoblich J., Mathews D., Montserrat N., Mosher J., Munsie M., Nakauchi H., Naldini L., Naughton G., Niakan K., Ogbogu U., Pedersen R., Rivron, N., Rooke H., Rossant J., Round J., Saitou M., Sipp D., Steffann J., Sugarman J., Surani A., Takahashi J., Tang F., Turner L., Zettler P., Zhai X. 2021. ISSCR Guidelines for Stem Cell Research and Clinical Translation: The 2021 update. Stem Cell Reports 16: 1398-1408.

Snyder J., Turner L. 2020. Crowdfunding, stem cell interventions and autism spectrum disorder: comparing campaigns related to an international “stem cell clinic” and US academic medical center. Cytotherapy 23, 3: 198-202.

Snyder J., Bateman-House A., Turner L. 2020. Is right to try being tried? Using crowdfunding data to better understand usage of nontribal pre-approval access pathways. Regenerative Medicine 15, 8: 1979-1985.

Turner L. 2020. Preying on Public Fears and Anxieties in a Pandemic: Businesses Selling Unproven and Unlicensed “Stem Cell Treatments” for COVID-19. Cell Stem Cell 26 (6): 806-810.

Smith C., Martin-Lille C., Higano J., Turner L., Phu S., Arthurs J., Nelson T., Shapiro S., Master Z. 2020. Challenging misinformation and engaging patients: characterizing a regenerative medicine consult service. Regenerative Medicine 15 (3): 1427-1440.

Sipp D., Turner L., Rasko, J. 2019 Stem Cell Businesses and Right to Try Laws. Cell Stem Cell 25 (3): 304-305.

Snyder J., Turner L. 2019. Crowdfunding for Stem Cell Based Interventions Intended to Treat Neurological Diseases and Injuries. Neurology 93, 6: 1-7.

Fu W., Smith C., Turner L., Fojtik J., Pacyna J., Master Z. 2019. Characteristics and Scope of Training of Clinicians Participating in the US Direct-to-Consumer Marketplace for Unproven Stem Cell Interventions. Journal of the American Medical Association 321, 24: 2463-2464.

Ikonomou L., Wagner DE., Turner L., Weiss DJ. 2019. Translating Basic Research into Safe and Effective Cell-based Treatments for Respiratory Diseases. Annals of the American Thoracic Society 16, 6: 657-668.

Tanner C, Munsie M, Sipp D, Turner L, Wheatland C. 2019. The politics of evidence in online illness narratives: an analysis of crowdfunding for purported stem cell treatments. Health: An Interdisciplinary Journal for the Social Study of Health, Illness and Medicine 23, 4: 436-457.

Zarzeczny A., Atkins H., Illes J., Kimmelman J., Master Z., Robillard J., Snyder J., Turner L., Zettler P., Caulfield P. 2018. The stem cell market and policy options: a call for clarity. Journal of Law and the Biosciences, 1-16.

Turner L. 2018. Direct-to-consumer marketing of stem cell interventions by Canadian Businesses. Regenerative Medicine 13 (6): 643-658.

Sipp D., Robey, P., and Turner L. 2018. Clear up this stem-cell mess. Nature 561 (7724): 455-457.

Wagner D., Turner L., Panoskaltsis-Mortari A., Weiss D., Ikonomou L. 2018. Co-opting of ClinicalTrials.gov by patient-funded studies. The Lancet Respiratory Medicine 6 (8): 579-581.

Turner L. 2018. The U.S. Direct-to-Consumer Marketplace for Autologous Stem Cell Interventions. Perspectives in Biology and Medicine 61, 1: 7-24.

Snyder J., Turner L. 2018. Selling stem cell ‘treatments’ as research: prospective customer perspectives from crowdfunding campaigns. Regenerative Medicine 13 (4): 375-384.

Snyder J, Turner L, Crooks V. 2018. Crowdfunding for Unproven Stem Cell-Based Interventions. Journal of the American Medical Association 319, 18: 1935-1936.

Knoepfler P., Turner L. 2018. The FDA and the US direct-to-consumer marketplace for stem cell interventions: a temporal analysis. Regenerative Medicine 13 (1): 19-27.

Weiss D., Turner L., Levine A., Ikonomou L. 2018. Medical Societies, Patient Education Initiatives, Public Debate, and the Marketing of Unproven Stem Cell Interventions. Cytotherapy 20 (2): 165-168.

Turner L. 2017. ClinicalTrials.gov, Stem Cells, and “Pay-to-Participate” Clinical Studies. Regenerative Medicine. 12 (6): 705-719.

Martins Martinho A., Turner L. 2017. Stem Cells in Court: Historical Trends in U.S. Legal Cases Related to Stem Cells. Regenerative Medicine 12 (4): 419-430.

Turner L., Knoepfler P. 2016. Selling Stem Cells in the USA: Assessing the Direct-to-Consumer Industry. Cell Stem Cell 19 (2): 154-157.

O’Donnell L., Turner L, Levine, A. 2016. The role of communication in better understanding unproven cellular therapies. Cytotherapy 18, 1: 143-148.

Dominici M., Nichols K., Srivastava A., Weiss D., Eldridge P., Cuende N., Deans R., Rasko J., Levine A., Turner L., Griffith D., O’Donnell L., Forte M., Mason C., Wagena E., Janssen W., Norton R., Wall, D., Ho H., Ruiz M., Wilton S., Horwitz E., Gunter K. 2015. Positioning a scientific community on unproven cellular therapies: The 2015 International Society for Cellular Therapy Perspective. Cytotherapy 1: 1663-1666.

Turner L. 2015. Federal Regulatory Oversight of U.S. Clinics Marketing Adipose-derived Autologous Stem Cell Interventions: Insights from Three New FDA Draft Guidance Documents. Mayo Clinic Proceedings 90, 5: 567-571.

Turner L. 2015. U.S. Clinics Marketing Unproven and Unlicensed Adipose-derived Autologous “Stem Cell” Interventions. Regenerative Medicine 10, 4: 397-402.

Turner L. 2015. U.S. Stem Cell Clinics, Patient Safety, and the FDA. Trends in Molecular Medicine 21, 5: 271-273.

Sipp D, and Turner L. 2012. U.S. Regulation of Stem Cells as Medical Products. Science 338: 1296-1297.