It's nice to see other groups reproduce our data about the conversion of human neurons directly from fibroblasts, and extend it to a linage-specific stage. Morphologically, the tyrosine hydroxylase-positive-induced neuronal cells converted by BAM+LF appear to be immature, and it is not clear if they can integrate into neuronal network, i.e., form synapses, and functionally release dopamine. More characterizations are needed, such as those performed by Wernig et al. (Wernig et al., 2008).

Wernig and colleagues' neurons derived from reprogrammed fibroblasts functionally integrate into the fetal brain and improve symptoms of rats with Parkinson's disease.

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