Retinal ganglion cells differentiated in vitro from retinal progenitor cells of the ciliary margin are competent to respond to axon guidance cues.

MEDORI, MARA; SANCHEZ, VIVIANA; DI NAPOLI, JENNIFER; SPELZINI, GONZALO; FIORE, LUCIANO; OLMOS CARREÑO, CINDY LORENA; TERUEL, LUISA R; SCICOLONE, GABRIEL

Buenos Aires

Congreso; LASDB (Latin American Society for Developmental Biology) Meeting 2019; 2019

Latin American Society for Developmental Biology

Retinal ganglion cells differentiated in vitro from retinal progenitor cells of the ciliary margin are competent to respond to axon guidance cues.JENNIFER DINAPOLI1,2 , CINDY OLMOS CARREÑO1,2 , MARA MEDORI1,2 , GONZALO SPELZINI1,2 , LUISA RENEÉ TERUEL1,2, VIVIANA SANCHEZ1,2, LUCIANO FIORE1,2 , GABRIEL SCICOLONE1,2. 1. CONICET ? Universidad de Buenos Aires, Instituto de Biología Celular y Neurociencias ?Prof. E. De Robertis? (IBCN). Ciudad de Buenos Aires, Argentina.2, Universidad de Buenos Aires, Facultad de Medicina, Departamento de Biología Celular, Histología, Embriología y Genética. Ciudad de Buenos Aires, Argentina.Directing progenitor cells in vitro to differentiate to specific neurons with the ability to establish topographic ordered connections is a major objective in any strategy for regeneration. The Ciliary Margin (CM) of the embryonic chick eye possesses progenitor cells which progressively lose the capability to differentiate into retinal ganglion cells (RGCs). Our objectives were: to obtain RGCs from neurospheres generated from the CM and to study whether these cells respond to specific axon guidance cues. We studied the Eph/ephrin system because it is the main molecular complex involved in retinotectal mapping. Neurospheres were produced from CM cells obtained from nasal and temporal sides of eyes from 7 and 12 days embryos. After expansion, neurospheres were cultured over polylisine-laminin substrates and different concentrations of insulin and Fibroblast Growth Factor 2 were assayed to determine the in vitro conditions to differentiate them into RGCs. These RGCs expresssd the components of the Eph/ephrin system according to the topographic origin of the progenitor cells. To determine whether these RGCs present topographic specific responses to axon guidance cues, RGCs were stimulated with EphA3 ectodomain (EphA3-Fc) or with ephrin-A2 (ephrin-A2- Fc). Nasal RGCs grew longer axons with EphA3-Fc and temporal ones grew shorter axons with ephrin-A2. This axonal behavior is similar to the response that RGCs have during retinotectal mapping. These results suggest that the RGCs differentiated from the progenitor cells of the CM are competent to respond to axon guidance cues. This opens the possibility that grafts of stem cells could differentiate into competent RGCs which could restitute neural circuits.Supported by Research Grants: PIP 0441 from CONICET and UBACYT 0526 and 0769.