Table 1 |.

Glial subtypes

Type	Enteric glial subtype		Defining features	Known or proposed functions
Intraganglionic	Myenteric	Type IMP	Small somata and extend very short, irregularly branched processes that surround neurons; associated with neuron cell bodies in the myenteric ganglia (‘protoplasmic-like’)	Modulate myenteric neuron activity10,11,14,17–19; regulate oxidative stress99,100; provide trophic support92–98,178; regulate neuroinflammation12,13,113,133,157; gliogenesis57, neurogenesis58,102,103,119 and replenishment of mucosal glia34
	Submucosal	Type ISMP	Associated with neuron cell bodies within submucosal ganglia	Modulate secretomotor neuron activity16
Extraganglionic	Interganglionic	Type II	Subtype that resides in interganglionic fibre tracts (‘fibrous’) with long processes that branch infrequently and run parallel to nerve fibres connecting enteric myenteric ganglia	Signal propagation in the glial network70; neuromodulation?
	Mucosal	Type IIImucosa	Extend a small number of long, fine unbranching processes; some follow nerve fibres and some terminate at the mucosal epithelium	Influence epithelial cell maturation36,46; potentially modulate immune responses19,37; probable modulation of neuroendocrine signaling21,35
	Enteric plexus	Type IIIMP/SMP	Subtype located in the extraganglionic regions at the level of myenteric and submucosal plexuses that run along neuronal fibres and/or wrap around small blood vessels	Unknown
	Intramuscular	Type IV	Extend a small number of long, fine unbranching processes that follow nerve fibres in the muscularis	Unknown

MP, myenteric plexus; SMP, submucosal plexus.