ABSTRACT
Stem cells are a group of undifferentiated cells with indefinite self-renewal and pluripotent differentiation ability.They are able to differentiate into precursor/progenitor cells and a variety of cell types and further regenerate new cells to be involved in the repair and rebuilding of injured tissue.Therefore,stem cells are becoming the major research objects in the study on tissue engineering therapy and regenerative medicine.As a sense organ composed of several kinds of neurons and other cells,eyes possesse the dominant superiority in stem cell transplantation therapy because of its good operation controllability and visuality,less demand for seed cells and low rejection after transplantation.These advantages have aroused growing interesting of the fundamental research and clinical trail in stem cell transplantation for irreversible eye diseases.Some exciting advances in the field of stem cell fundamental research,several phase Ⅰ/Ⅱ clinical trials are in progress.The patients with degenerative eye diseases for phase Ⅰ clinical trials are in recruiting in China to evaluate future curative effect and security of stem cell-based therapies.Currently,several issues in stem cell-based eye disease therapies are still pending.We discuss the updated development of stem cell-based transplantation in ophthalmology and future researching direction in order to help ophthalmological researchers to understand the concepts and research strategies.
ABSTRACT
Objective:To observe the phenomena of lens regeneration in rabbits in vivo and the influence of vitamin A on it.Methods:Intracapsular lens extraction were done.Following the operation,0.1ml vitamin A oil was given by subcutaneous injection into abdomen every other day in experimental group,while 0.1ml saline was given in control group.This procedure lasted 2 months.The animals were observed regularly after operation and were put to death at the 16th week follwing the operation.The state of lens regeneration were analyzed by means of tissue sections and ultrathin sections.Results:There were 3 and 1 eye(s)in which regenerated lens-like substance was found in the back of iris respectively in experimental group and in control group.The regenerated substance was estimated to be typical lens sturcture after the light microscopical and electron microscopical analysis.Conclusion:Our experiment suggests that the substance possessing typical lens structure can be regenerated after lens extraction in rabbit,although the intact regenerated lens is not found at present.Vitamin A can accelerate this course in vivo.