Review Article

Stem Cell Therapy for Treatment of Ocular Disorders

Table 1

Manipulation of different type of extraocular stem cells for treating ocular disorders in preclinical and clinical trials.

Stem cellsExperimental design/research or disease modelRoute of injectionResearch outcomesReferences/sources

Hematopoietic stem cells (HSCs)Chemically damaged retinal neuron in miceIntravenous injectionFusion with ganglion, amacrine, and Müller glial cells, heterokaryons reprogramming, and dedifferentiation into neuroectodermal lineageSanges et al. [82]
Delivery of granulocyte-colony stimulating factor in rats with retina ischemiaIntravenous injectionApoptosis of retinal cells was reduced and improved visual function Localization of HSCs in the retinal layerLin et al. [94]
Transplantation of human HSCs in mice with acute retinal ischemia-reperfusion injury Intravenous injectionHSC-treated group of mice showed improved retinal histopathology. However there was no significant difference compared to control mice. No intraocular tumor and no abnormal proliferation of human cells in major organs Park et al. [83]
Transplantation in retinal degenerative conditions (atrophic ARMD, Retinitis Pigmentosa) or retinal vascular disease (diabetes, vein occlusion)Intravitreal injectionClinical trial to measure primary outcome on adverse events is still ongoingNCT01736059 (ClinicalTrials.gov)

Induced pluripotent stem cells (iPSCs)Injection of mouse fibroblast iPSC-conditioned medium Intravenous injectionMaintenance of retina integrity and function by reducing apoptosis of retinal neurons following photodamageChang et al. [91]
Swine iPSCs-derived photoreceptors Subretinal injectionIntegration of photoreceptors was observed in chemically damaged retinaZhou et al. [90]
Generation of 3-dimensional neural retina sheet derived from mouse iPSCs and ESCs for subretinal transplantation into retinal degenerative miceSubretinal injectionDevelopment into outer nuclear layer (ONL) with completely structured inner and outer segments of photoreceptorAssawachananont et al. [95]
Generation of photoreceptor cell from adult mouse dermal fibroblast-derived iPSCs for subretinal transplantation into retinal degenerative miceSubretinal injectionDevelopment of functional photoreceptor in miceTucker et al. [96]
Generation of RPE sheets from human iPSCs for transplantation into wet ARMD patientsSubmacular injectionPilot safety study involving six patients is currently ongoing. RPE were observed to be retained in patientsKamao et al. [141]

Embryonic stem cells (ESCs)In vitro differentiation of rostral neural progenitors into retinal neuron cellsNot availableIncreased cell expression of CRX, S-opsin, and Rho/Rcvrn in hypoxic culture condition, indicating differentiationGarita-Hernández et al. [93]
Treatment of patients affected by Stargardt’s macular dystrophy and atrophic ARMD with human ESCs-derived RPE suspensionSubmacular injectionImproved visual function. No signs of hyperproliferation, tumorigenicity, ectopic tissue formation, and immune rejection were observedNCT01344993, NCT01345006
(ClinicalTrials.gov)
Treatment of patients affected by wet ARMD with human ESCs-derived RPE sheetsIntraocular injectionClinical trial is still ongoing. This method of delivery is hoped to overcome the disadvantages of using ESC-derived RPE suspensionNCT01691261
(ClinicalTrials.gov)

Mesenchymal stem cells (MSCs)Injection of bone marrow-derived MSCs into a laser-induced ocular hypertensive glaucoma of rat modelIntravitreal injectionIncrease in retina ganglion cell (RGC) axon survival and significant decrease in the rate of RGC axon loss normalized to cumulative intraocular pressure exposureJohnson et al. [97]
Transplantation of bone marrow-derived MSCs into Retinopathy of Prematurity (ROP) rat modelNot availableReduced apoptosis in retinal cells with higher expression of neurotrophin-3 and CNTF in ROP ratsZhao et al. [86]
Direct topical application of MSCs or MSCs-conditioned medium on cornea for two hoursCorneal surfaceReduced inflammation, opacity, and neovascularization in chemically burned corneaOh et al. [85]
Transplantation of bone marrow-derived MSCs in rats following optic nerve crushIntravitreal injectionRescued degeneration of retinal ganglion cells and axon regenerationMesentier-Louro et al. [88]
Transplantation of bone marrow-derived MSCs in alkali-induced oxidative stress rabbit corneasCorneal surfaceReduced apoptosis in corneal epithelial cells, vascularization, and infiltration of macrophagesCejkova et al. [87]
In vitro differentiation of adult human bone marrow stem cells with retinal pigmented epithelium cells Coculture experimentDifferentiated cells expressed neuronal and photoreceptor phenotypesChiou et al. [98]
Transplantation of MSCs overexpressing pigment epithelium derived factor in animal models of choroid neovascularizationNot availableInhibition of neovascularization and MSCs adopted RPE phenotypesLiu et al. [76]
Delivery of human adipose-derived MSCs to light-induced in vitro and in vivo models Intravitreal injectionInhibition of photoreceptor degeneration and retinal dysfunction Sugitani et al. [99]
Transplantation of human umbilical cord blood-derived MSCs to neurodegenerative rat model Intraperitoneal injectionPromotion of regeneration and protection of damaged retinal ganglion cellsZwart et al. [166]
In vivo delivery of human umbilical cord-derived MSCs to early retinal degenerative rat modelSubretinal injectionPreservation and rescue of photoreceptor degeneration and improvement in visual functionsLund et al. [167]
Delivery of ADSCs into atrophic ARMD patients. The cells are harvested from liposuction tissuesIntravitreal injectionClinical trial to measure primary outcomes on adverse events; visual acuity and visual field analysis is still ongoingNCT02024269
(ClinicalTrials.gov)

Adipose-derived stem cells (ADSCs)Injection of BMSCs in patients with advanced ARMD (atrophic or neovascular)Intravitreal injectionClinical trial to measure primary outcome on visual acuity is still ongoingNCT01518127
(ClinicalTrials.gov)

Bone marrow stem cells (BMSCs)Unilateral ocular transplantation into patients with advanced atrophic AMDSubretinal injectionClinical trial to measure primary outcome on adverse events is still ongoingNCT01632527
(ClinicalTrials.gov)

Central nervous system stem cells (hCNS-SCs)Unilateral ocular transplantation into patients with advanced atrophic AMDSubretinal injectionClinical trial to measure primary outcome on adverse events is still ongoingNCT01632527
(ClinicalTrials.gov)