The Gregg Semenza Lab studies the molecular mechanisms of oxygen homeostasis. We have cloned and characterized hypoxia-inducible factor 1 (HIF-1), a basic helix-loop-helix transcription factor. Current research investigates the role of HIF-1 in the pathophysiology of cancer, cerebral and myocardial ischemia, and chronic lung disease, which are the most common causes of mortality in the U.S.

The Johns Hopkins Center for Epithelial Disorders focuses on research into the physiology and pathophysiology of epithelial cells (cells that line the cavities and interior surfaces of the body) of the gastrointestinal (GI) tract, liver, pancreas and kidney. Specifically, the center’s research seeks to: -Understand the mechanisms regulating the activity of transport proteins (including channels) of epithelial cells Characterize the mechanisms by which polarity of epithelial cells are maintained -Investigate the mechanisms controlling transcription of epithelial-specific genes Understand the pathophysiological basis of GI and renal diseases that involve the preceding three components -The center also provides a framework for training fellows in gastroenterology and hepatology to become independent investigators. The center is funded primarily through individual investigator-initiated extramural research grant support from the National Institutes of Health (NIH) as well as multi-investigator grants including RO1, PO1, UO1 and R24.

The Dölen lab studies the synaptic and circuit mechanisms that enable social behaviors. We use a variety of techniques including whole cell patch clamp electrophysiology, viral mediated gene transfer, optogenetics, and behavior. We are also interested in understanding how these synaptic and circuit mechanisms are disrupted in autism and schizophrenia, diseases which are characterized by social cognition deficits. More recently we have become interested in the therapeutic potential of psychedelic drugs for diseases like addiction and PTSD that respond to social influence or are aggravated by social injury, We are currently using both transgenic mouse and octopus to model disease.

Research in the Vestibular NeuroEngineering Lab (VNEL) focuses on restoring inner ear function through “bionic” electrical stimulation, inner ear gene therapy, and enhancing the central nervous system’s ability to learn ways to use sensory input from a damaged inner ear. VNEL research involves basic and applied neurophysiology, biomedical engineering, clinical investigation and population-based epidemiologic studies. We employ techniques including single-unit electrophysiologic recording; histologic examination; 3-D video-oculography and magnetic scleral search coil measurements of eye movements; microCT; micro MRI; and finite element analysis. Our research subjects include computer models, circuits, animals and humans. For more information about VNEL, click here. VNEL is currently recruiting subjects for two first-in-human clinical trials: 1) The MVI Multichannel Vestibular Implant Trial involves implantation of a “bionic” inner ear stimulator intended to partially restore sensation of head movement. Without that sensation, the brain’s image- and posture-stabilizing reflexes fail, so affected individuals suffer difficulty with blurry vision, unsteady walking, chronic dizziness, mental fogginess and a high risk of falling. Based on designs developed and tested successfully in animals over the past the past 15 years at VNEL, the system used in this trial is very similar to a cochlear implant (in fact, future versions could include cochlear electrodes for use in patients who also have hearing loss). Instead of a microphone and cochlear electrodes, it uses gyroscopes to sense head movement, and its electrodes are implanted in the vestibular labyrinth. For more information on the MVI trial, click here. 2) The CGF166 Inner Ear Gene Therapy Trial involves inner ear injection of a genetically engineered DNA sequence intended to restore hearing and balance sensation by creating new sensory cells (called “hair cells”). Performed at VNEL with the support of Novartis and through a collaboration with the University of Kansas and Columbia University, this is the world’s first trial of inner ear gene therapy in human subjects. Individuals with severe or profound hearing loss in both ears are invited to participate. For more information on the CGF166 trial, click here.

Dr. Cebotaru is the Director of Johns Hopkins Center for Gene Therapy research in Gastroenterology and research in the Cebotaru Lab studies cystic fibrosis transmembrane conductance regulator (CFTR) mutants as well as the pathophysiology of polycystic liver and kidney disease (PKD). They also investigate corrector molecules to get a better understanding of their mechanism of action. A major focus of her research is on developing more efficient gene therapy vectors with the ultimate goals of developing a gene therapy for cystic fibrosis and PKD.

Our research focuses on the biology of the peptidoglycan of Mycobacterium tuberculosis, the organism that causes tuberculosis, and Mycobacteroides abscessus, a related bacterium that causes opportunistic infections. We study basic mechanisms associated with peptidoglycan physiology but with an intent to leverage our findings to develop tools that will be useful in the clinic to treat mycobacterial infections. Peptidoglycan is the exoskeleton of bacteria that not only provides structural rigidity and cell shape but also several vital physiological functions. Breaching this structure is often lethal to bacteria. We are exploring fundamental mechanisms by which bacteria synthesize and preserve their peptidoglycan. Although our lab uses genetic, biochemical and biophysical approaches to study the peptidoglycan, we pursue questions irrespective of the expertise required to answer those questions. It is through these studies that we identified synergy between two beta-lactam antibiotics against select mycobacteria.

Research in the Nicholas Dalesio Lab is currently examining pre-surgical predictors of post-surgical respiratory complications in children with obstructive sleep apnea and sleep-disordered breathing; the impact of anesthesia and pharmacological agents on upper airway physiology; and techniques for pediatric airway imaging.

We investigate the brain networks and neurotransmitters involved in symptoms of movement disorders, such as Parkinson's disease, and the mechanisms by which modulating these networks through electrical stimulation affects these symptoms. We are particularly interested in the mechanisms through which neuromodulation therapies like deep brain stimulation affect non-motor brain functions, such as cognitive function and mood. We use imaging of specific neurotransmitters, such as acetylcholine and dopamine, to understand the changes in brain chemistry associated with the clinical effects of deep brain stimulation and to predict which patients are likely to have changes in non-motor symptoms following DBS. Through collaborations with our neurosurgery colleagues, we explore brain function by making recordings during DBS surgery during motor and non-motor tasks. Dr. Mills collaborates with researchers in the Department of Neurosurgery, the Division of Geriatric and Neuropsychiatry in the Department of Psychiatry and Behavioral Sciences and in the Division of Nuclear Medicine within the Department of Radiology to translate neuroimaging and neurophysiology findings into clinical applications.

The Hui lab performs basic, translational and clinical research on genetics and genomics of neurogastroenterological disorders. Ongoing projects include evaluation of sensory mechanisms in the pathophysiology of nausea using single-cell sequencing analysis of the vagal nodose ganglion cells and real world clinical data in order to understand mechanisms of this debilitating and poorly understood condition.

Lauren Jantzie, professor of pediatrics and vice chair of research for the Department of Pediatrics, received her Ph.D. in neurochemistry from the University of Alberta in 2008. In 2013 she completed her postdoctoral fellowship in the Department of Neurology at Boston Children's Hospital & Harvard Medical School and became faculty at the University of New Mexico. Dr. Jantzie then joined the faculty Departments of Pediatrics (Neonatal-Perinatal Medicine) and Neurology at Johns Hopkins University and the Kennedy Krieger Institute in January 2019.

The Jantzie lab investigates the pathophysiology of encephalopathy of prematurity, and pediatric brain injury common to infants and toddlers. Dr. Jantzie is dedicated to understanding disease processes in the developing brain as a means to identifying new therapeutic strategies and treatment targets for perinatal brain injury. Her lab studies neural substrates of cognition and executive function, inhibitory circuit formation, the role of an abnormal intrauterine environment on brain development, mechanisms of neurorepair and microglial activation and polarization.

Using a diverse array of clinically relevant techniques such as MRI, cognitive assessment, and biomarker discovery, combined with traditional molecular and cellular biology, the Jantzie lab is on the front lines of translational pediatric neuroscience.