Sam Horng

Sam Horng, MD, PhD

  • ASSISTANT PROFESSOR | Neurology, Multiple Sclerosis



Research Topics:

Blood-Brain Barrier, Brain Imaging, Chemokines, Cytokines, Demyelination, Immunology, Multiple Sclerosis, Neuro-degeneration/protection, Neurobiology, Neurology, Neuroscience

Sam Horng, MD, PhD, received his B.A. in biology, summa cum laude, from Columbia University, then trained as a pre-doctoral fellow in clinical bioethics at the National Institutes of Health. He completed his MD and PhD degree at Harvard Medical School and the Massachusetts Institute of Technology, where his graduate research investigated how early patterning events specify different sensory areas of the thalamus and cortex. 

Dr. Horng completed his medical internship at Yale New Haven Hospital and his neurology residency at Mount Sinai Hospital, where he served as chief resident and was awarded an R25 Research in Residency grant from the National Institutes of Health and a Leon Levy Neuroscience Fellowship from 2015 to 2017 to study mechanisms of blood-brain barrier breakdown in inflammatory brain disease.

Dr. Horng investigates the role of specialized blood-brain barrier cells called astrocytes in controlling immune cell entry into the brain during autoimmune attack. He recently published work featured on the cover of The Journal of Clinical Investigation, demonstrating for the first time, that astrocytes act as an inducible barrier to immune cell entry in the early stages of autoimmune attack.

His laboratory is now focused on identifying specific contact-mediated interactions between astrocytes and immune cells, hypothesizing that astrocytes activate immune cells and control subsequent steps in the process of autoimmune attack. He aims to translate this work towards treatment strategies for multiple sclerosis and other CNS autoimmune diseases.

Dr. Horng offers telemedicine appointments when appropriate. Please call his office to schedule a video visit.

Dr. Horng is registered to provide telehealth services in Florida.

Clinical Focus

  • Demyelinating Disease
  • Gadolinium Enhancing Lesions
  • Lumbar Puncture

Multi-Disciplinary Training Area

Neuroscience [NEU]


MD,PHD, Harvard Medical School

BA, Columbia University

PhD, Massachusetts Institute of Technology

Internship, Internal Medicine, Yale-New Haven Hospital

Residency, Neurology, Mount Sinai School of Medicine

Fellowship, Multiple Sclerosis, Mount Sinai School of Medicine

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