Yizhi Liu
Zhongshan Ophthalmic Center, China
Title: Lens regeneration using endogenous stem cells for treatment of congenital cataract
Biography
Biography: Yizhi Liu
Abstract
The repair and regeneration of tissues using endogenous stem cells represents an ultimate goal in regenerative medicine. However, tissue or organ regeneration using endogenous stem cells in human has not been demonstrated. Currently, the only treatment for cataracts, the leading cause of blindness worldwide, is to extract the cataractous lens and implant an artificial intraocular lens. This procedure poses significant risks of complications for young patients. Here we isolate lens epithelial stem/ progenitor cells (LECs) in mammals and show that Pax6 and Bmi-1 are required for LEC renewal. We designed a surgical method of cataract removal that preserves endogenous LECs and achieved functional lens regeneration in rabbits and macaques, as well as in human infants with cataract. Compared with the traditional procedure, we move the anterior capsulorhexis from the center to the periphery, reducing the diameter to 1-1.5mm, preserving the capsule, sub-capsular cells, and the physiological barrier between the anterior and the posterior segment. For infants and young children, this procedure reduces post-operative inflammation and the incidence of postoperative complications such as iris adhesion and secondary ocular hypertension while protecting the local milieu required for lens regeneration. Our approach conceptually differs from current practice, as it maximally preserves endogenous LECs and their natural environment, and regenerates lenses with visual function. Our findings demonstrate a novel treatment strategy for cataract and provide a new paradigm for tissue regeneration using endogenous stem cells.