Transplantation of @entity19 embryonic stem (mES) cells can restore function in @entity191 models, but can generate @entity44 . Purification of @entity935 neurons derived from embryonic stem cells by fluorescence-activated cell sorting (FACS) could provide a functional cell population for transplantation while eliminating the risk of @entity44 formation. Here we used the @entity669 hydroxylase (TH) promoter to drive enhanced green fluorescent protein (eGFP) expression in mES cells. First, we evaluated 2.5-kilobase (kb) and 9-kb TH promoter fragments and showed that clones generated using the 9-kb fragment produced significantly more eGFP+/TH+ neurons. We selected the 9-kb TH clone with the highest eGFP/TH overlap for further differentiation, FACS, and transplantation experiments. Grafts contained large numbers of eGFP+ @entity935 neurons of an appropriate phenotype. However, there were also numerous eGFP+ cells that did not express TH and did not have a neuronal morphology. In addition, we found cells in the grafts representing all three germ layers. Based on these findings, we examined the expression of stem cell markers in our eGFP+ population. We found that a majority of eGFP+ cells were stage-specific embryonic antigen-positive ( @entity11823 +) and that the genetically engineered clones contained more @entity11823 + cells after differentiation than the original D3 mES cells. By negative selection of @entity11823 , we could isolate a neuronal eGFP+ population of high purity. These results illustrate the complexity of using genetic selection to purify mES cell-derived @entity935 neurons and provide a comprehensive analysis of cell selection strategies based on @entity669 hydroxylase expression. Disclosure of potential conflicts of interest is found at the end of this article.

Selection of embryonic stem cell-derived enhanced green fluorescent protein-positive @entity935 neurons using the XXXX hydroxylase promoter is confounded by reporter gene expression in immature cell populations.

@entity11823 :: ('14345(Tax:10090)', 'Gene') :: ['SSEA-1'] @entity19 :: ('10090', 'Species') :: ['mouse'] @entity935 :: ('MESH:D004298', 'Chemical') :: ['dopamine'] @entity191 :: ('MESH:D010300', 'Disease') :: ['Parkinson disease'] @entity669 :: ('CHEBI:18186', 'Chemical') :: ['tyrosine'] @entity44 :: ('MESH:D013724', 'Disease') :: ['teratoma', 'teratomas']
@entity669 :: (CHEBI:18186,Chemical) :: ['tyrosine']
