Generation of human β-thalassemia induced pluripotent stem cells from amniotic fluid cells using a single excisable lentiviral stem cell cassette.

Induced pluripotent stem cells (iPSCs) derived from somatic cells of patients represent a powerful tool for biomedical research and may have a wide range of applications in cell and gene therapy. However, the safety issues and the low efficiency associated with generating human iPSCs have limited their usage in clinical settings. The cell type used to create iPSCs can significantly influence the reprogramming efficiency and kinetics. Here, we show that amniotic fluid cells from the prenatal diagnosis of a β-thalassemia patient can be efficiently reprogrammed using a doxycycline (DOX)-inducible humanized version of the single lentiviral "stem cell cassette" vector flanked by loxP sites, which can be excised with Cre recombinase. We also demonstrated that the patient-derived iPSCs can be characterized based on the expression of pluripotency markers, and they can be differentiated into various somatic cell types in vitro and in vivo. Moreover, microarray analysis demonstrates a high correlation coefficient between human β-thalassemia iPS cells and human embryonic stem (hES) cells but a low correlation coefficient between human β-thalassemia amniotic fluid cells and human β-thalassemia iPS cells. Our data suggest that amniotic fluid cells may be an ideal human somatic cell resource for rapid and efficient generation of patient-specific iPS cells.