Corneal stromal mesenchymal stem cells: reconstructing a bioactive cornea and repairing the corneal limbus and stromal microenvironment

Corneal stroma-derived mesenchymal stem cells(CS-MSCs) are mainly distributed in the anterior part of the corneal stroma near the corneal limbal stem cells(LSCs). CS-MSCs are stem cells with self-renewal and multidirectional differentiation potential. A large amount of data confirmed that CS-MSCs can be induced to differentiate into functional keratocytes in vitro, which is the motive force for maintaining corneal transparency and producing a normal corneal stroma. CS-MSCs are also an important component of the limbal microenvironment. Furthermore, they are of great significance in the reconstruction of ocular surface tissue and tissue engineering for active biocornea construction. In this paper, the localization and biological characteristics of CS-MSCs, the use of CS-MSCs to reconstruct a tissue-engineered active biocornea, and the repair of the limbal and matrix microenvironment by CS-MSCs are reviewed, and their application prospects are discussed.

Cryopreserved limbal lamellar keratoplasty for peripheral corneal and limbal reconstruction

This study aimed to evaluate the outcomes and described the recovery process of cryopreserved limbal lamellar keratoplasty（CLLK） for peripheral corneal and limbal diseases. Thirteen eyes of 12 patients with a mean age of 41±23.9 y were included. The average follow-up was 12.1±5.6 mo. Stable ocular surface was achieved in all eyes at last follow-up. Epithelialization originated from both recipient and graft in 9 eyes. We conclude that CLLK compensates for the shortage of donor corneas and cryopreserved limbal grafts provide epithelialization sources in ocular surface reconstruction.

A new rat model of glaucoma induced by intracameral injection of silicone oil and electrocoagulation of limbal vessels

Background A satisfied glaucoma model is absent now.The aim of this study was to evaluate the effect of a combination of intracameral injection of silicone oil and electrocoagulation of corneal limbal vessels and episcleral veins in the rats to establish glaucoma model.Methods Operation was performed in each of the left eyes of 90 adult male rats.Right eyes were used as controls.Measurement of intraocular pressure （IOP） was performed with an applanation tonometer （Tong-Pen）.Retinal ganglion cells （RGCs） were retrogradely labeled by applying FluoroGold onto the bilateral superior colliculus.Results During the follow-up （24 weeks）,the lOP of the study eyes was significantly higher （P〈0.05） than the control eyes （at final examination,IOP of control eyes was （13.4±1.0） mmHg and lOP of study eyes was （16.1±1.8） mmHg）.Correspondingly,at 24 weeks after operation,the RGCs density of the study eyes （2286.11±290.45/mm^2） was significantly lower than the control eyes （2626.46±164.85/mm^2,P〈0.01）.In the operated eyes,histological examination showed excavation of optic disc and increased neuroglial cells in the optic nerve,reduced thickness of retina and diminution of retinal ganglion cells,and atrophy of ciliary body and iris.Notably,the anterior chamber angle of the operated eye remained open.Conclusions A combination of intracameral injection of silicone oil and electrocoagulation of comeal limbal vessels and episcleral veins may establish a reliable glaucoma model for further research.