Michelle Olsen

  • Associate Professor for the School of Neuroscience, College of Science, Virginia Tech

  • Director of Graduate Studies for the School of Neuroscience, College of Science, Virginia Tech

Research in the Olsen lab is focused on understanding the role of astrocytes in normal and abnormal central nervous system function. Astrocytes are one of the most abundant cell types in the mammalian brain and spinal cord, yet, until recently, this cell type has been thought of as a support cell to neurons and they have been given relatively little attention.  Emerging work suggests astrocytes contribute to all facets of normal brain function, while disrupted astrocyte function is implicated in epilepsy, neurodegenerative disease, depression, and neurodevelopmental disorders. 


Stefanie Robel

  • Assistant Professor, Fralin Biomedical Research Institute at VTC

  • Assistant Professor, School of Neuroscience, College of Science, Virginia Tech

Proper brain function is mediated by neurons and shaped by glial cells. Astrocytes are glial cells in the brain that have many roles during development and in the mature brain. The Robel lab studies the fascinating changes that astrocytes undergo when the brain is injured by trauma and consequences of trauma such as post-traumatic epilepsy and neurodegeneration. We ask how these changes affect astrocyte functions: (1) at the synapse where astrocytes are responsible for maintaining ion and neurotransmitter homeostasis  (2) at the network level - Do local changes in astrocyte function affect neuronal network function? (3) at the vasculature where astrocytes contribute to maintenance of the blood-brain barrier and regulation of blood flow.


Harald Sontheimer

  • Executive Director, School of Neuroscience

  • Professor, Fralin Biomedical Research Institute at VTC

  • Director, Center for Glial Biology in Health, Disease, and Cancer, Fralin Biomedical Research Institute at VTC

  • I. D. Wilson Chair in the College of Science, Virginia Tech

  • Commonwealth Eminent Scholar in Cancer Research

The Sontheimer laboratory is interested in the contribution of glial cells to neurological illnesses including brain cancer. Current projects are examining changes that occur as glial cells transform into primary brain tumors, glioma. Owing to their invasiveness and rapid growth, gliomas are among the most deadly cancers in humans. Utilizing clinically relevant animal models, and we have described the pathways for tumor invasion and underlying mechanism that aid this deadly process, and have developed an experimental treatment that has been successful in phase I and II clinical trials.

In a second line of research we are studying the role of glia in acquired epilepsy, particularly as a result of lesions, tumors or brain infection. These studies focus on impairment in vascular function and the role of impaired glutamate handling of glia.

Finally, we are investigating how aging affects normal glia and how amyloid deposits in Alzheimer disease impairs normal astrocyte function thereby contributing to the disease process.


Research Teams Studying Glia at the Fralin Biomedical Research Institute and Virginia Tech


Susan C. Campbell

  • Assistant Professor. Department of Animal and Poultry Science and School of Neuroscience

Our brain cells communicate with one another by a process known as synaptic transmission.  Synaptic transmission forms the basis of our thoughts and perception. In human patients with epilepsy, aberrant synaptic transmission contributes to seizures.

The focus of my research is to:  1) to understand the molecular mechanisms of altered synaptic communication that leads to the development of epilepsy and identify targets that may  serve as therapeutic targets for treatment 2) to elucidate the mechanism that make a subset of epilepsy patients refractory to treatment (patients that cannot control their seizures with common anti-epileptic drugs) and 3)  to decipher the role of the gut microbiota in seizure susceptibility in acquired and idiopathic epilepsies (epilepsies of unknown cause).  

Projects will aim to: 1) determine how changes in the gut microbiota influences the function of neuron and glia cells to shape synaptic function in different neuronal circuits in normal and epilepsy models, 2) examine how specific diets affects the composition of the gut microbiota and regulate neuronal function and seizure threshold, 3) decipher how bacterially released molecules such as short-chain fatty acids can regulate neuronal function to shape neuronal hyperexcitability, and 4) determine differences in the quantity and diversity of microbes in epilepsy models.


Mike Fox

  • Associate Professor, Fralin Biomedical Research Institute at VTC

  • Director, Developmental and Translational Neurobiology Center, Fralin Biomedical Research Institute at VTC

  • Associate Professor, Biological Sciences, College of Science, Virginia Tech

  • Associate Professor, Department of Pediatrics, Virginia Tech Carilion School of Medicine

Synapses are specialized sites that allow information to be passed between neurons. Their importance is highlighted by the fact that even minor synaptic abnormalities, caused by disease or neurotrauma, result in devastating neurological conditions. Understanding how CNS synapses are formed is therefore essential to our understanding of neurological disorders. The Fox Laboratory is interested in understanding the cellular and molecular mechanisms that drive two aspects of synapse formation—synaptic targeting and synaptic differentiation. 
Efforts to uncover mechanisms that drive the initial targeting of synapses in the Fox laboratory focus primarily on the developing subcortical visual system. Specifically, we are interested in understanding how synapses are formed between retinal ganglion cells (RGCs), the output neurons of the retina, and target neurons within the brain. Despite monumental advances in this field, it still remains unclear how different subtypes of RGCs—of which there are more than 30—target functionally distinct nuclei within the brain. One brain region where class-specific targeting of RGC axons is most evident is the lateral geniculate complex (LGN) — a cluster of thalamic nuclei that contains three structurally and functionally distinct retino-recipient nuclei (dLGN, vLGN and IGL). Since different classes of RGCs target these nuclei, we hypothesized that regionalized guidance cues must exist to direct subtype-specific axonal targeting. We have identified several candidate molecules that may act as targeting cues for subtype-specific retinal targeting and are now testing their necessity in retinogeniculate circuit formation.
Once synaptic partners have correctly targeted each other, both sides of the synapse must exchange developmentally relevant signals that transform this immature connection into a functioning synapse (a process called synaptic differentiation). We are interested in identifying such trans-synaptic organizing cues in the mammalian brain (in both visual and no-visual brain regions) and how the loss or mutation of these factors leads to neurodevelopmental and neuropsychiatric disorders. 
In addition to projects that explore neural circuit formation, we are also exploring how infectious agents and trauma alter circuits in the adult brain.  For example, in one project we are exploring how the obligate intracellular parasite Toxoplasma gondii alters the anatomy and physiology of inhibitory brain circuits.  Latent infection by T. gondii is associated with subtle, pathological behavioral abnormalities and increases the risk for develop neurodevelopmental and neuropsychiatric disorders.


Blake Johnson

  • Assistant Professor. Department of Industrial & Systems Engineering

The Johnson Lab is focused on improving our understanding of glial cell chemotaxis in systems involving multiple chemoattractants of varying spatiotemporal profile toward the goal of understanding higher-order physiological and pathophysiological processes in the central and peripheral nervous systems.   Computer-aided bio-fabrication processes, sensors (material property and biosensors), and mathematical modeling tools are used to create in vitro models, tissue scaffolds, and sensor-integrated cell culture platforms for studying glial cell chemotaxis in engineered macro- and micro-environments that mimic native nerve.  We also apply this new knowledge and technical capability for the development of nerve repair technology (e.g., nerve guidance conduits) for repair of complex gap injuries and polymer-based neural interfaces for bio-electronic and bionic therapeutics (e.g., brain-machine interfaces).


Samy Y. Lamouille

  • Assistant Professor, Basic Science Education, Virginia Tech Carilion School of Medicine

  • Research Assistant Professor, Biological Sciences, College of Science, Virginia Tech

  • Research Assistant Professor, Fralin Biomedical Research Institute at VTC


Paul Morton

  • Assistant Professor, Department of Biomedical Sciences & Pathobiology

Oligodendrocytes are white matter producing glial cells that wrap axons with myelin during development. In a variety of perinatal insults, we find disruption of neural stem cell pools affecting both neurons and oligodendrocytes. Morton Lab is interested in how neural precursor migration and proper myelination occurs in the gyrified cortices, and their underlying white matter tracts, of higher order mammals during normal brain development and in disease. Our research is translational in nature and employs preclinical animal model systems along with cutting-edge, large-scale imaging approaches to identify key factors responsible for altered brain maturation during critical developmental milestones.


Michelle H. Theus

  • Associate Professor, Molecular and Cellular Neurobiology. Department of Biomedical Sciences & Pathobiology.

The Theus lab explores the consequence of brain injury on vascular-glial and radial glial-like stem cell behaviors. Emphasis is placed on understanding how cell-to-cell contact proteins influence the local interaction of glia cells within the blood brain barrier and neurogenic niches. Our team interrogates how dysregulation of vascular-glial communication affects key biological processes such as inflammation, aberrant migration and cell growth properties. Our overarching goal is to restore homeostasis and regain function in numerous neurological diseases of the brain.


Pam VandeVord

  • Professor and Head, Virginia Tech - Wake Forest University School of Biomedical Engineering and Sciences (SBES)

Research in the VandeVord lab focuses on complex injury mechanisms to the brain that lead to concussions, with a thrust to understand the persistent neurobehavioral and neuropathological consequences of the traumatic event. We study the fundamental questions concerning the mode of energy transfer to the brain during traumatic injuries as well as the consequent damage or disruptive mechanisms at the cellular and molecular levels. We investigate the dynamic changes that occur within cells and their environment which lead to dysfunction. Furthermore, our work strives to provide mechanistic insight for outcomes such as elevated anxiety, cognitive deficits and fear triggered by the traumatic event. Collectively, these efforts will help the community understand how the brain becomes injured and we work to provide a platform to design novel strategies to protect from, identify and treat the injury and alleviate the negative behavioral outcomes.