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at Emory University

Studying human glia with functional brain models

Glia are the most abundant cell types in the mammalian nervous system. They are integral to normal brain physiology, yet we still understand very little about how they develop, what functions they perform, and how they are involved in disease. We understand even less about these cells in humans because of the lack of direct access to intact, functioning human brain tissue.


Our lab is using pluripotent stem cells (iPSCs) derived non-invasively from skin samples to generate brain cells in the lab. Because the brain is a 3D structure and studying cells growing on a plate doesn't recapitulate its complexity, we are using human iPSCs to generate functional 3D structures that are patterned to mirror specific regions of the human brain. We can culture these 'brains-in-a-dish' for long periods of time to ask how normal brain development is occurring in a human system. 


We are pursuing two big picture topics. First, how do human glia develop and what makes them unique?  Secondly, given that glia play critical roles in helping neural circuit development, does abnormal glial development contribute to neurodevelopmental disorders like autism and schizophrenia? To answer these questions, we are using state-of-the-art genome engineering, stem cell biology, imaging, and neurobiological approaches. Our hope is that by investigating the potential contribution of this previously overlooked group of cells in the nervous system, we may be able to decipher new mechanisms and therapeutic targets to advance human health.


                     ||   Our goals and commitment


Our team is powered by the shared experiences, knowledge, challenges, and achievements of each of our members. Diversity is key to our success, and we believe that we must take direct actions to build an inclusive environment both within our own group and within our greater academic community.

Addressing racism, implicit bias, and discrimination is important to our group. We believe this should be approached through efforts including advocacy, recruitment, education, and outreach. This includes education on micro/macro aggressions in academia, implicit bias, and the impact of racism on science. It also involves advocating for URM scientists within and outside our local community and promoting their work broadly. We also feel strongly about engaging with future trainees from minority backgrounds who perhaps have never had significant exposure to a career in science or academia. 

As one concrete step towards that goal, we are accruing a list of STEM opportunities for high school and undergraduate students who are interested in learning and participating in scientific research. This list, linked below, identifies opportunities that are specific to Emory (or Atlanta-based individuals) and others that are open to all students. Please let us know if other programs should be included so that we can keep this resource up-to-date and comprehensive!

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                     ||   Assistant Professor

Dr. Steven Sloan is an Assistant Professor in the Department of Human Genetics, at the Emory University School of Medicine. He was born in Phoenix, Arizona and spent the latter half of his childhood in South Florida. For his undergraduate degrees in Biomedical Engineering and Biochemistry he attended the University of Miami, FL.


Steven received his MD and PhD degrees at Stanford University in the laboratory of Ben Barres, where he became fascinated with glia--the understudied and mysterious cell types that adjoin neurons within the nervous system. Given his interests in human medicine, Steven spent his PhD investigating the functions of human astrocytes. Along with his colleagues, he developed techniques to purify and profile each of the major CNS cell types from the rodent and human brain and created resources to distribute this information so that it could be utilized by the entire neuroscience community. 


Recognizing that studying human glia from primary tissue had inherent limitations, Steven completed a post-doctoral fellowship with Dr. Sergiu Pasca at Stanford to develop a human induced pluripotent stem cell 3D model of cortical development called human cortical spheroids (hCS). This is an ideal system for interrogating human cortical development and specifically glial development in both healthy and diseased states. Steven joined the Emory faculty in the fall of 2018, where his lab studies glial development and the role these cells play in neurodevelopmental and neuropsychiatric disease.


In his free time, Steven can be found training for triathlons and spending time outdoors and with his family (including the lab's first two members, canines Kevin and Ben). 

Lab Members

I graduated with a B.S. in Biochemistry with an emphasis in Biology at the University of California, Riverside. In my spare time I love reading, journaling, watching The Office, and practicing yoga.


Research: My current project involves utilizing molecular and cell biological techniques to identify progenitor populations responsible for the production of human astrocytes.

 ||   Lead Research Specialist

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I graduated from the Institute of Chemical Technology (Mumbai, India) and then received my PhD in Pharmacology from Duquesne University in Pittsburgh, PA where I studied sex-specific effects of chaperone and microglial defenses in Lewy body disorders. In my spare time I enjoy cooking, reading, writing, and traveling to new places.

Research: I am using region-specific human brain organoids to determine vulnerabilities to glioblastomas across space and time.

 ||   Postdoc


I graduated from the University of Michigan with a B.S. in Cellular and Molecular Biology and spent 2 additional years as a postbaccalaureate researcher. When I'm not in the lab, I enjoy gardening, watching sports, trying new foods, and relaxing with my cat!


Research: my project is focused on identifying chromatin modifiers that are responsible for changes in the chromatin landscape that result in astrocyte reactivity.

 || Graduate Student

I graduated with a degree in biochemistry from McMaster University and completed my PhD in Helen McNeill's lab at the University of Toronto investigating the role of cadherins in mitochondrial biology. In my postdoc work in Julie Lefebvre's lab I studied how protocadherins direct the development of cortical interneuons in the mammalian brain. In my spare time I enjoy exploring local restaurants and can also be found gaming (both board and video).

 || Research Specialist


I am an undergraduate studying Biology and Interdisciplinary Studies. I am interested in studying developmental lead (Pb) exposure In my spare time, I enjoy biking, watching movies, trying new food, and exploring new plaecs.

 ||   Undergraduate


I am an undergraduate studying Anthropology and Human Biology. I am interested in studying the effect of endothelial cells in promoting cerebral organoid viability. In my spare time, I love to exercise outdoors, read, try new places to eat, and spend time with friends and family.

 ||   Undergraduate

I am an undergraduate studying Neuroscience and Behavioral Biology and Sociology. I am interested in studying astrocyte maturation and GBM in the organoid model. In my free time, I enjoy exploring coffee shops, painting, re-watching Friends, and trying new food!

 ||   Undergraduate

Kevin the Dog has never held a pipette before, but he has spent his life perfecting the delivery of moral, emotional, and physical support (snuggles). He looks forward to meeting new people who share his passion for glia and is always willing to give his TED Talk on how 'work-life-balance' should be reframed as 'sleep-life-balance'. 

 ||   Lab Mascot

I graduated with a B.S. in Animal Science and minors in Spanish and Biological Sciences at LSU. I am interested in studying neurodevelopment and how its dysregulation leads to neurological disorders, such as autism spectrum disorder. In my free time, I enjoy hiking, playing/watching sports, volunteering, and traveling. 


Research:  My current project focuses on using dCas9-effector systems to modulate gene expression during neuroectoderm differentiation.

 ||  Graduate Student

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I graduated with a B.S. in Marine Biology from California State University Long Beach and spent 2 years as a postbaccalaureate fellow at the NIH. I am interested in the molecular underpinnings of glial cell development and how this is dysregulated in neurodevelopmental disorders. In my spare time, I enjoy hiking, reading, and running.


Research: My current project uses several genomic profiling methods to investigate the developmental origins of GBM

 ||  Graduate Student

I graduated with a B.S.E in Biomedical Engineering from the University of Michigan. I am interested in 3D in vitro models to study neurodevelopment and diseases. In my spare time, I enjoy cooking/baking, watching and playing sports, kickboxing, and traveling. 


Research: My current project focuses on integrating 3D bioprinting and iPSCs to study neurodevelopment. 

 ||   Graduate Student


I graduated from UCLA with a PhD in Molecular Toxicology, where I studied serotonergic neuromodulation of fly visual processing. Prior to graduate school, I earned a BS in Biochemistry and worked at the CDC measuring toxicants in human blood as part of the NHANES biomonitoring program. 


Research: I am studying effects of developmental lead toxicity within the context of neuron-astrocyte interactions. 

 ||   Postdoc


I am currently an undergraduate majoring in Neuroscience and Behavioral Biology, and I am interested in learning about how manipulating genes associated with neurodevelopment affects the brain. When I'm not busy, I love to bake, hang out with friends, binge Netflix shows and find new places to eat in Atlanta

 ||   Undergraduate


I graduated from UMBC with a BS in Biochemistry and then received an MD/PhD from Vanderbilt where I studied noninvasive methods of visualizing retinal pathology as a biomarker for Alzheimer's disease. Currently I am in the Emory Neurology Residency Program and am interested in pursuing a research fellowship in neuroimmunology. In my spare time I enjoy running and travelling with my wife.


Research: My current project focuses on understanding the pathophysiologic mechanism of neurotoxicity in hyperammonemia. 

 || Postdoc, Resident


I graduated with a B.S. in Molecular and Cell Biology from Yale University and spent the following two years as a postgraduate researcher. At Emory, I developed an interest in brain development and in utilizing in-vitro systems to model early developmental processes.

Research: My current project focuses on characterizing glial progenitor populations and mechanisms underlying cell fate decisions.

 || Graduate Student

at Emory University
The Sloan Lab, along with the Andersen and Birey Labs, is part of a tri-lab stem cell-based modeling effort at the Department of Human Genetics at Emory. Our labs work closely and synergistically on questions related to understanding the processes underlying the assembly of the central nervous system in health and disease. To accomplish these goals, we use a variety of human stem cell models including region-specific organoids and assembloids, along with state-of-the-art technologies including single cell genomics, live-imaging, genomic engineering, and new molecular tools.  

Combining our collective expertise in the field, our three groups have together created the “
Brain Organoid Hub” where we aim to standardize, automate and innovate on the maintenance, differentiation, and use of hiPSCs, organoids and assembloids. hiPSC and organoid maintenance is time consuming, and reproducibility and reliability of the cultures is key for experiment success. For this reason, one of the primary goals of the hub is to deprioritize time spent by lab members on media changes and quality control so that they can better focus on running assays, designing experiments, reading and thinking. At the same time, the hub provides a unique opportunity to improve upon standards and practices of differentiation protocols, reduce handling variability and increase throughput. If you have any further questions about the Brain Organoid Hub, please reach out!
Brain Organod Hub



July 2023

New publication!
We have a new publication on the extrinsic signals that direct astrocyte development out now in Nature Neuroscience. Check it out here! Also a wonderful briefing that summarizes our findings. 

Selected Publications

||                                ||   

Voss, A..J., Lanjewar, S.N., Sampson, M.M., King, A., Hill, E.J., Sing, A., Sojka, C., Bhatia, T.N., Spangle, J.M., Sloan, S.A. Identification of ligand–receptor pairs that drive human astrocyte development (2023), Nature Neuroscience

Cadena, M., Ning, L.., King, A., Hwang, B., Jin, L,, Serpooshan, V*., Sloan, S.A.* 3D Bioprinting of Neural Tissues (2020), Advanced Healthcare Materials. *Co-corresponding authors

Review of 3D bioprinting in the nervous system

Lanjewar, S.N., Sloan, S.A. Growing Glia: Cultivating Human Stem Cell Models of Gliogenesis in Health and Disease (2021), Frontiers in Cell and Developmental Biology. 

Gupta I., Collier PG*, Haase B., Mahfouz A., Joglekar A., Floyd T., Koopmans F., Barres B., Smit AB, Sloan SA, Luo W., Fredrigo O, Ross ME, Tilgner HU. Single-cell isoform RNA sequencing characterizes isoforms in thousands of cerebellar cells. (2021) Nature Biotechnology

Sloan, S.A., Huber, N., Caneda, C., …, Barres, B.A., Pasca, S. Human Astrocyte Maturation Captured in 3D Cerebral Cortical Spheroids Derived from Pluripotent Stem Cells (2017) Neuron

Using 3D organoid cultures to study human astrocytes

Sloan, S.A., Andersen, J., Birey, F., … Pasca, S. ­­Generation and Assembly of Human Brain Region-Specific 3D Cultures (2018) Nature Protocols

Protocol for generating human cortical spheroids
Using sc-RNAseq to find infiltrating GBM cells in human samples

Darmanis, S*, Sloan, S.A.*, … Quake, S.A. Single-Cell RNAseq analysis of diffuse neoplastic infiltrating cells at the migrating front of human glioblastoma (2017) Cell Reports. *Co-first authors

Zhang,Y*, Sloan, S.A.*, Clarke,L., Caneda, C., … Barres, B.A. Purification and characterization of progenitor and mature human astrocytes reveals transcriptional and functional differences with mouse. (2016) Neuron *Co-first authors

Purifying human astrocytes and other human CNS cell types

Pasca, A.*, Sloan, S.A.*, Clarke, L., Tian, Y., Makinson, … Barres, B.A., Pasca, S. Functional cortical neurons and astrocytes from human pluripotent stem cells in 3D cultures. (2015). Nature Methods *Co-first authors

Original method for generating human cortical spheroids

Zhang, Y*., Chen, K.*, Sloan, S. A*., Bennett, M. L., Scholze, A. R., … Wu, J. Q. An RNA-Sequencing Transcriptome and Splicing Database of Glia, Neurons, and Vascular Cells of the Cerebral Cortex. (2014) The Journal of Neuroscience *Co-first authors

Brosius Lutz, A., Chung, W., Sloan, S.A., … Barres, B.A., Schwann cells use TAM receptor-mediated phagocytosis in addition to autophagy to clear myelin in a mouse model of nerve injury (2017). PNAS

Transcriptomic profiling of all major CNS cell types in mouse

Darmanis, S., Sloan, S.A., … Barres, B.A., Quake, S. A survey of human brain transcriptome diversity at the single cell level. (2015) PNAS

Single cell RNAseq of the healthy human brain

Zuchero, B., Fu, M.M., Sloan, S.A., … Barres, B.A. CNS myelin wrapping is driven by myelin basic protein-induced actin disassembly. (2015) Developmental Cell

Lui, H., Zhang, J., … Sloan, S.A., … Barres, B.A., Huang, E.J. Progranulin deficiency promotes circuit-specific synaptic pruning by microglia via complement activation. (2016) Cell

Madelaine, R., Sloan S.A., … Barres, B.A., Mourrain, P. Micro RNA-9 Couples Brain Neurogenesis and Angiogenesis. (2017) Cell Reports

Review of stem cell models of gliogenesis
Reviews and Commentaries

Sloan, S. A., Barres, B. A. (2017). Assembling a Cellular User Manual for the BrainJ. Neuroscience

Sloan, S. A., Barres, B. A. (2014b). Looks can be deceiving: reconsidering the evidence for gliotransmissionNeuron

Sloan, S. A., Barres, B. A. (2014). Mechanisms of astrocyte development and their contributions to neurodevelopmental disordersCurrent Opinion Neurobiology

Sloan, S. A., Barres, B. A. (2014). The Detrimental Role of Glial Acidification during IschemiaNeuron

Sloan, S.A., Barres, BA. (2013). Glia as primary drivers of neuropathology in TDP-43 proteinopathiesPNAS


Transcriptomic Databases of Human and Mouse brain



We are seeking motivated, inquisitive , and collaborative people to help us study human neurodevelopment through the lens of glia.


 Our goal is to provide a diverse and inclusive working environment in which all scientists can thrive and are treated with respect.


If you are an Emory graduate student interested in learning about opportunities in the lab, please email Steven. If you are looking for a graduate position and you are not at Emory already, you will need to apply to the biosciences graduate program at Emory. More information about program can be found here.


Candidates with an excellent research record and a desire to ask rigorous scientific questions should email Steven with a brief introduction, CV, and the names and contact information of at least two references


We are located at the Emory University campus in Druid Hills, Georgia
Whitehead Biomedical Research Building
Room 375
615 Michael Street
Atlanta, GA, 30322

Office phone: (404) 727-7208



Cover photo: iDISCO of human cortical spheroid stained for GFAP. Credit: Fikri Birey 

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