Dr. Payam Mohassel

Nicholas Maragakis treats patients with motor neuron diseases, such as amyotrophic lateral sclerosis (ALS). This care is coordinated with the Johns Hopkins Center for ALS Specialty Care, a multidisciplinary clinic with expertise in treating patients with ALS and providing support to their caregivers. He serves as medical director of the ALS Clinical Trials Unit, an extension of the multidisciplinary clinic that seeks to facilitate opportunities for patients with ALS to participate in clinical trials that could advance the treatment of this disease. Dr. Maragakis is interested in the basic science of understanding neurodegenerative diseases, as well as the translational potential of therapeutic compounds developed in the laboratory. His fundamental research interest is in using stem cells — more specifically, stem cell-derived motor neurons and glia — for understanding the development and propagation of ALS. His laboratory has been involved in creating and characterizing lines of stem cells from patients with ALS using induced pluripotent stem cell (iPSC) methodologies. The laboratory has a large library of iPSCs from patients with familial ALS and from patients with sporadic ALS. The utilization of this library of iPSCs has facilitated the development of a spinal cord-specific iPSC-astrocyte/motor neuron co-culture system, which has been leveraged for the development of assays that can be used for both the basic understanding of ALS astrocyte and motor neuron biology as well as, eventually, drug screening for ALS therapeutics. His laboratory has taken its long-standing interests in astrocyte biology, as it relates to ALS, to develop a program that investigates astrocyte-specific mechanisms as contributors to the progression (both temporally and anatomically) of disease in ALS. In this vein, there is an interest in astrocytic glutamate transporters and, more recently, astrocyte hemichannels and gap junctions. Dr. Maragakis is rated as an Elite provider by MediFind in the treatment of Primary Lateral Sclerosis. His top areas of expertise are Amyotrophic Lateral Sclerosis (ALS or Lou Gehrig's Disease), Primary Lateral Sclerosis, 15q11.2 Microdeletion, and Spinal Muscular Atrophy (SMA).

Dr. Charlotte Sumner is a Professor of Neurology and Neuroscience at Johns Hopkins University School of Medicine. Dr. Sumner cares for patients with genetically-mediated neuromuscular diseases. Her practice is notable for a focus on individuals with inherited neuromuscular disorders of peripheral nerves and motor neurons, including spinal muscular atrophy (SMA) and Charcot-Marie-Tooth (CMT) disease. She co-directs the Johns Hopkins Muscular Dystrophy Association Care Center, the Spinal Muscular Atrophy (SMA), and the Charcot-Marie-Tooth (CMT) clinics, which deliver multidisciplinary clinical care, engage in international natural history studies, and provide cutting edge therapeutics. Dr. Sumner’s research focuses on developing treatments for degenerative disorders of motor neurons and peripheral nerves. Her laboratory uses human tissues and induced pluripotent cell lines, mouse models and cultured cells to characterize disease mechanisms and develop treatments. Dr. Charlotte Sumner received her medical degree from the University of Pennsylvania School of Medicine following undergraduate studies at Princeton University. She completed internal medicine internship and neurology residency at the University of California San Francisco, after which she returned to the east coast for a neuromuscular fellowship at Johns Hopkins and a neurogenetics fellowship in the Neurogenetics Branch at the National Institute of Neurological Disorders and Stroke. She joined the neurology faculty at Johns Hopkins in 2006. Dr. Sumner is rated as a Distinguished provider by MediFind in the treatment of Primary Lateral Sclerosis. Her top areas of expertise are Spinal Muscular Atrophy (SMA), Charcot-Marie-Tooth Disease, Primary Lateral Sclerosis, Spinal Muscular Atrophy Type 2, and Gastrostomy.

Arens Taga is a neurologist specializing in neuromuscular diseases, with a particular focus on amyotrophic lateral sclerosis (ALS) and other motor neuron diseases. His clinical work aims to improve the quality of care for patients with ALS through biomarker-based, precision medicine approaches that refine disease stratification and facilitate more targeted and efficient enrollment in clinical trials. As a clinician-scientist, Dr. Taga uses patient-derived induced pluripotent stem cells to model ALS, uncover novel disease mechanisms and identify therapeutic targets that are translatable to clinical trials. In recognition of his work in ALS, Dr. Taga was awarded the 2025 Richard Olney Clinician Scientist Development Award, which honors early-career physician-scientists dedicated to advancing ALS research. Dr. Taga earned his medical degree from the School of Medicine and Surgery at the University of Parma, Italy, where he also completed his neurology residency. He subsequently trained at The Johns Hopkins University, completing a postdoctoral research fellowship in the neuromuscular division, an internal medicine internship, a neurology residency and a neuromuscular clinical fellowship. Dr. Taga is rated as a Distinguished provider by MediFind in the treatment of Primary Lateral Sclerosis. His top areas of expertise are 15q11.2 Microdeletion, Primary Lateral Sclerosis, Amyotrophic Lateral Sclerosis (ALS or Lou Gehrig's Disease), and Cluster Headache.