Highly Efficient Directed Neural Differentiation Of Rat Embryonic Stem Cells In Serum-free Medium Culture

Nuerodegenerative diseases are a class of chronic, progressive nervous system diseases. Recently , with the increasing degree of aging of society, nervous degenerative diseases have being occupied an increasingly important position in all of the diseases. Traditionally there was no ability of regeneration of nerve cells, so the research was basically focused on the improvement of the damage to the neurodegenerative diseases and prevention of enhance of the damage. Until 1990s, with the discovery of neural stem cells that people changed this concept, but the damage on the nervous system diseases have had yet no effective treatment, so the central nervous system injury and repair still is the great challenge for us people.Because of the establishing of Embryonic Stem Cells, researchers have begun to research cell replacement therapy using Embryonic Stem Cells. Embryonic Stem Cells are a kind of totipotent stem cells. Their differentiation into neurons can used as a extensive cell resources for nerve transplantation, if transplanted neural cells can function normally, they will cure a lot of nervous system diseases fundamentally.Current neural induction protocols for embryonic stem cells rely on embryoid body formation, stromal feeder co-culture , cell factors inducing selective survival conditions or transgenic approaches. Each strategy has considerable drawbacks, such as cell line- dependent variability of differentiation results, poorly defined culture conditions, low efficiency of neural induction and safe problems. The use of embryonic stem cells (ESCs) as a source of neurons for cell therapy will require the development of simple and reliable cell differentiation protocols.Here we describe a new kind of ES cell differentiation system that can provides both fast, efficient neural induction and the ability to generate neural stem cells. We also developed protocols for harvesting dopamine neurons and motor neurons. Firstly, we directly differentiate rES cells into neurospheres ; then adding different cytokines to get dopaminergic neurons and motoneuron neurons, and using lentivirus taking red fluorescent protein (H794) to infect neurospheres. After that we can transplant these cells with initial differentiation into the brain of Rat. The aim of that is study the survival and differentiation of neuro stem cells. This method is sufficient to induce rapid and complete neural conversion of RES cells under adherent culture conditions.This method of neural induction should promote the use of Rat ES cells in regenerative medicine and disease modeling and remove the need for protocols based on embryoid bodies or stromal feeders. This work suggests that Rat ESCs can differentiate in simple serum-free suspension cultures to produce the large number of cells required for transplantation studies.