TABLE 1.

Main studies in brain organoid transplantation.

Transplanted organoids	Cell type derived	Extracellular scaffold	Receiver	Evaluation time post implantation	Blood supply	Immunosuppressive treatment	Main finding	References
Brain organoids at 47–48 DIV	hESCs hiPSCs	Matrigel	P8–P10 CD1 mice	2 and 4 weeks	Host brain	None	Increased cell survival and neuronal differentiation	Daviaud et al., 2018
Brain organoids at 40–50 DIV	hESCs	Matrigel	NOD/SCID mice	0.5–8 months	Host brain	None	Increased neuronal differentiation and maturation; developed functional synaptic connectivity and neuronal activity between grafted and host brain	Mansour et al., 2018
Brain organoids at 55 DIV	hESCs	Matrigel	Sprague–Dawley rats	4 weeks	Host brain	Cyclosporine A	Reduced cerebral infarct volume; enhance axonal regeneration and synaptic reconstruction	Wang S. N. et al., 2020
Brain organoids at 55 and 85 DIV	hESCs	Matrigel	Sprague–Dawley rats	8 weeks	Host brain	Cyclosporine A	Increased neurogenesis and cell survival; improved motor function and reduced brain injury; 55-day brain organoids are better donors than that of 85-day;	Wang Z. et al., 2020
Brain organoids at 42 and 70 DIV	hESCs	ND	SCID mice; cynomolgus monkeys	12 weeks	Host brain	None; tacrolimus hydrate	Extended axons along the host corticospinal tract; 42-day organoids caused graft overgrowth after transplantation	Kitahara et al., 2020
Brain organoids at 40–50 DIV	hESCs hiPSCs	ND	SCID mice	1–5 months	ND	None	Increase the startle fear response of host; showing subcortical projection establishment	Dong et al., 2020

DIV, days in vitro; ND, not described.