Uno studio del 2011 mostra come sia possibile ottenere neuroni e cellule della glia partendo da cellule staminali pluripotenti indotte, ottenute a loro volta da cellule epidermiche umane prese tramite biopsia.
[Karumbayaram S, Lee P, Azghadi SF, Cooper AR, Patterson M, Kohn DB, Pyle A, Clark A, Byrne J, Zack JA, Plath K, Lowry WE. From skin biopsy to neurons through a pluripotent intermediate under Good Manufacturing Practice protocols. Stem Cells Transl Med. 2012 Jan;1(1):36-43. doi: 10.5966/sctm.2011-0001. Epub 2011 Dec 7.]
“The clinical application of human-induced pluripotent stem cells (hiPSCs) requires not only the production of Good Manufacturing Practice-grade (GMP-grade) hiPSCs but also the derivation of specified cell types for transplantation under GMP conditions. Previous reports have suggested that hiPSCs can be produced in the absence of animal-derived reagents (xenobiotics) to ease the transition to production under GMP standards. However, to facilitate the use of hiPSCs in cell-based therapeutics, their progeny should be produced not only in the absence of xenobiotics but also under GMP conditions requiring extensive standardization of protocols, documentation, and reproducibility of methods and product. Here, we present a successful framework to produce GMP-grade derivatives of hiPSCs that are free of xenobiotic exposure from the collection of patient fibroblasts, through reprogramming, maintenance of hiPSCs, identification of reprogramming vector integration sites (nrLAM-PCR), and finally specification and terminal differentiation of clinically relevant cells. Furthermore, we developed a primary set of Standard Operating Procedures for the GMP-grade derivation and differentiation of these cells as a resource to facilitate widespread adoption of these practices.”
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“Here, we report that patient-specific neural progenitor cells (NPCs) and neurons can be derived from hiPSCs using methods that are completely devoid of xenobiotics and are GMP-compatible. These approaches apply novel techniques to derive fibroblasts from patients, reprogram them to a pluripotent state, and then differentiate them to NPCs and neurons, all in completely defined media and without animal products or feeder cells.”
“We procured xenobiotic-free cell culture reagents for the cell culture needed for the stages from derivation of fibroblasts from skin biopsies to their reprogramming into hiPSCs and the differentiation to NPCs, neurons, and glia.”
“NPCs are capable of generating both neurons and glial cells.”
“To our knowledge, this is the first description of procedures necessary to take patient biopsies and generate NPCs, neurons, and glia through a pluripotent intermediate in the complete absence of either xenobiotics or feeder cells, with commercially available reagents. As new xeno-free media formulations, and even clinical grade feeders, are now regularly brought to market, it is possible that the conditions used here are not the only feasible methods to achieve this end. This is the first report to document the site of integration for the reprogramming factors after xeno-free reprogramming and demonstrate that such integrations can be benign. As a result, this work can serve as a starting point for clinical application of hiPSCs. The presentation here of clinical-grade SOPs could help to ensure that these methods are applied consistently and appropriately.”