RESUMO
Objective: motor neuron differentiation from human embryonic stem cells [hESCs] is a goal of regenerative medicine to provide cell therapy as treatments for diseases that damage motor neurons. Most protocols lack adequate efficiency in generating functional motor neurons. However, small molecules present a new approach to overcome this challenge. The aim of this research is to replace morphogen factors with a cocktail of efficient, affordable small molecules for effective, low cost motor neuron differentiation
Materials and Methods: in this experimental study, hESCs were differentiated into motor neuron by the application of a small molecule cocktail that consisted of dorsomorphin, A8301, and XAV939. During the differentiation protocol, we selected five stages and assessed expressions of neural markers by real-time polymerase chain reaction [PCR], immunofluorescence staining, and flow cytometry. Motor neuron ion currents were determined by whole cell patch clamp recording
Results: immunofluorescence staining and flow cytometry analysis of hESC-derived neural ectoderm [NE] indicated that they were positive for NESTIN [92.68%], PAX6 [64.40%], and SOX1 [82.11%] in a chemically defined adherent culture. The replated [hESC]-derived NE differentiated cells were positive for TUJ1, MAP2, HB9 and ISL1. We evaluated the gene expression levels with real-time reverse transcriptase-PCR at different stages of the differentiation protocol. Voltage gated channel currents of differentiated cells were examined by the whole-cell patch clamp technique. The hESC-derived motor neurons showed voltage gated delay rectifier K[+], Na[+] and Ca[2+] inward currents
Conclusion: our results indicated that hESC-derived neurons expressed the specific motor neuron markers specially HB9 and ISL1 but voltage clamp recording showed small ionic currents therefore it seems that voltage gated channel population were inadequate for firing action potentials