formation of neural crests from human pluripotent stem cells for enteric nervous system research

Derivation of Enteric Neurons from Human Pluripotent Stem Cells

The enteric nervous system (ENS) is the largest component of the peripheral nervous system. The ENS contains more than 400 million neurons that are located within the GI tract and control nearly all functions of the gut1. Molecular understanding of the ENS development and function and its defects in enteric neuropathies requires access to a reliable and authentic source of enteric neurons. Access to human primary tissue is limited, and animal models fail to recapitulate key disease phenotypes in many enteric neuropathies. Human pluripotent stem cell (hPSC) technology has proven exceedingly beneficial in providing an unlimited source of desired cell types, especially those that are difficult to isolate from primary sources2,3,4,5,6,7. Here, we provide details of a stepwise and robust in vitro method to obtain ENS cultures from hPSCs. These scalable hPSC-derived cultures open avenues for developmental studies, disease modeling, and high-throughput drug screening and can provide transplantable cells for regenerative medicine.
Enteric neuron lineages are derived from neural crest (NC) cells following the ENS developmental path during embryogenesis. In embryos, NC cells emerge along the margins of the folding neural plate. They proliferate, migrate and give rise to many different cell types including sensory neurons, Schwann cells, melanocytes, craniofacial skeleton and enteric neurons and glia8,9,10. The cell fate decision depends on the distinct region along the anterior-posterior axis that the NC cells emerge from, i.e., cranial NC, vagal NC, trunk NC and sacral NC. The ENS develops from vagal and sacral NC cells with the former dominating the population of the enteric neurons owing to the extensive migration along the length of the bowel and colonizing the gut11.
Derivation of NC cells from PSCs commonly involves a combination of dual SMAD inhibition and WNT pathway activation12,13. Until recently, all NC induction protocols involved serum and other animal product additives in the culture conditions. Chemically undefined media not only lower the reproducibility of NC induction but also challenge mechanistic developmental studies. To overcome these challenges, Barber et al14 developed an NC induction protocol using chemically defined culture conditions and was hence advantageous over alternative methods that rely on serum-replacement factors (e.g., KSR)13,14. This was obtained by basal media replacements and optimizing a protocol originally presented by Fattahi et al to derive enteric NC cells from hPSCs. This improved system is the basis of the hPSC differentiation protocol that is presented here. It begins with induction of enteric neural crest (ENC) cells in a 15-day period by precise modulation of BMP, FGF, WNT and TGF&#946; signaling in addition to retinoic acid (RA). We then derive the ENS lineages by treating cells with glial cell line-derived neurotrophic factor (GDNF). All media compositions are chemically defined and yield robust enteric neuronal cultures within 30-40 days.
In addition to the monolayer cell culture system described here, alternative NC induction approaches have been developed which use free-floating embryoid-bodies15,16. Migratory cells in these cultures have been shown to express NC markers with a subset representing the vagal NC. Co-cultures with primary gut tissue have been used to enrich enteric NC precursors in these cultures. Media compositions in these studies contain a combination of different factors such as nerve growth factor, NT3 and brain-derived neurotrophic factor. At this stage, it is not fully clear how these factors might affect the enteric neuron precursor commitment identities. For an efficient comparison of the enteric NC induction in the monolayer and the embryoid-body-based cultures more data is required. Given the different culture layouts in these strategies, the use of each method should be considered and optimized according to specific application in mind.
The protocol presented here is reproducible and has been successfully tested by us and others using different hPSC (induced and embryonic) lines8,14,16.

Author Spotlight: Robust Culture of Human Enteric Neurons from Human Pluripotent Stem Cells

Differentiation of Enteric Nervous System Lineages from Human Pluripotent Stem Cells

Here we provide a method for generation of human enteric neurons from human pluripotent stem cells under fully defined conditions, and we use these cells in order to understand human enteric nervous system development and function. So I think human enteric nervous system development, physiology and pathophysiology has been a great challenge, and it's because of the rarity of the enteric nervous system cells and the transient nature of the neural crest progenitors, and difficulty in access to tissue and isolation of the tissue. This is a robust platform for generating authentic and functional human enteric neurons from HPSCs, and by overcoming longstanding technical challenges in tissue access, it provides scalable cultures of enteric nervous system components for disease modeling, drug discovery, and studying ENS developments and function.

Formation of Neural Crests from Human Pluripotent Stem Cells for Enteric Nervous System Research

To induce neural crest formation, replace the maintenance medium of the human pluripotent stem cell culture with 200 microliters of medium A per square centimeter of the well-surface. Incubate the culture under 5%carbon dioxide supplementation at 37 degrees Celsius for two days. Gently aspirate the medium from the well-containing 100%confluence cells then pipette about 200 microliters of medium B per square centimeter of the well-surface area.On day four, feed the cells with 200 microliters of medium B per square centimeter of the well-surface. Incubate the cells for two more days, then replace the medium B with 400 microliters per square centimeter of medium C.

Research

JoVE Journal

Neuroscience

The human enteric nervous system, ENS, is a large network of glial and neuronal cell types with remarkable neurotransmitter diversity. The ENS controls ...