Induced Pluripotent Stem Cells Take a Big Step Towards Clinical Applications

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March 04 2009 / by Bora (Memebox)

This week, researchers from Canada and Scotland made a major advancement in the field of stem cell biology. They discovered a method to successfully reprogram somatic cells into stem cells without the use of viruses.

Induced pluripotent stem cells (iPSCs) are a type of stem cells derived from adult somatic cells by forcing expression of genes shown to sufficiently reprogram somatic cells into stem cells. iPSCs have been shown to possess key characteristics of embryonic stem cells (ESCs), the most important of which is the ability to give rise to cells of all three germ layers. iPSCs are an ideal source of stem cells because they circumvent the need for human embryos to generate stem cells. Additionally, because they can be generated from one’s own somatic cells which are readily available, iPSCs can be used for patient-specific therapies, thereby reducing the risk of immune rejection.

The method by which iPSCs are derived currently, however, presents a major safety concern: the stem cell marker genes required to reprogram somatic cells are delivered using viral vectors. When these viral vectors are inserted in a random fashion, it can result in incidental expression of proto-oncogenes, such as Myc, leading to tumor formation. In the current studies, researchers used DNA fragments called transposons that can be inserted into the genome to deliver the reprogramming genes and subsequently removed.

While this study represents a significant step towards a wider utilization of iPSCs in clinical applications and the field of regenerative medicine in general, it remains necessary to clarify whether induced expression of reprogramming genes is a contributing factor in the increased incidents of tumor formation.

http://www.memebox.com/futureblogger/show/1697-induced-pluropotent-stem-cells-take-a-big-step-towards-clinical-applications

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http://www.youtube.com/watch?v=iTIhv4l7qPs

http://www.youtube.com/watch?v=iTIhv4l7qPs