Stem cell therapy in ocular pathologies in the past 20 years

Table 2 Retinal diseases and therapies

Ophthalmic disease	Ref.	Stem cells used	In animals or in humans	Conclusions
Retina	Van Meurs et al[109], 2004	RPE cells	Humans	A pigmented area was seen in the extraction bed of the neovascular membrane in only one patient
	Tucker et al[110], 2011	iPSCs	Animals	Adult fibroblast-derived iPSCs provide a viable source for the production of retinal precursors to be used for transplantation and treatment of retinal degenerative disease
	Lamba et al[111], 2006	hESCs	Animals	hES cell derived retinal progenitors integrate with the degenerated mouse retina and increase in their expression of photoreceptor-specific markers
	Nakano et al[48], 2012	IPSCs/hESCs	Humans	We demonstrate that an optic cup structure can form by self-organization in hESC culture
	Gonzalez-Cordero et al[113], 2013	ESCs	Animals	We show that rod precursors integrate within degenerate retinas of adult mice and mature into outer segment-bearing photoreceptors
	Schwartz et al[40], 2015	hESCs	Humans	First evidence of the medium-term to long-term safety, graft survival, and possible biological activity of pluripotent stem cell progeny in individuals with macular diseases
	Schwartz et al[114], 2012	hESCs	Humans	The hESC-derived RPE cells showed no signs of hyperproliferation, tumorigenicity, ectopic tissue formation, or apparent rejection after 4 mo
	Gaddam et al[120], 2019	Adult stem cells	Humans	The paracrine nature of adipose stem cells, in particular, has been highlighted as a potential solution to the lack of a homing and conducive environment that poses a challenge to the implantation of exogenous stem cells in the target tissue

hESCs: Human embryonic stem cells; iPSC: induced pluripotent stem cell; RPE: Retinal pigment epithelium.