Monday, February 27, 2006

What "60 Minutes" didn't tell you on Feb. 26, 2006

"60 Minutes" talked about embryonic stem cells on February 26, 2006, including a dicussion of work by Hans Keirstead. They didn't mention the patent applications of Keirstead or where the stem cell lines came from.

--> Oligodendrocytes derived from human embryonic stem cells for remyelination and treatment of spinal cord injury
Keirstead, Hans S., 20050101014 (May 12, 2005)
Application 10/661105 (filed Sept 12, 2003)

35. A differentiated cell population as part of a system for generating glial cells, wherein at least .about.80% of cells in the differentiated cell population are oligodendrocyte precursors having the following characteristics: they are progeny of primate pluripotent stem (pPS) cells; they stain with antibody specific for NG2 proteoglycan; and they are negative for the neuronal marker NeuN; and wherein the system further comprises the line of pPS cells from which the differentiated cells were produced.

[0001] This application is a continuation of PCT application serial no. PCT/GB2003/003021, filed Jul. 10, 2003 (Atty Docket No. IRVN-009WO, entitled "Oligodendrocytes Derived from Human Embryonic Stem Cells fro Remyelination and Treatment of Spinal Cord Injury," which application was filed in English and designating the United States, which application is a continuation-in-part of U.S. application Ser. No. 10/406,817, filed Apr. 4, 2003, which application claims the benefit of U.S. provisional application Ser. No. 60/395,382, filed Jul. 11, 2002. [Giving this application pre-Hwang priority.]

Oligodendrocytes derived from human embryonic stem cells for remyelination and treatment of spinal cord injury
20040009593 (Jan. 15, 2004)
This invention provides populations of neural cells bearing markers of glial cells, such as oligodendrocytes and their precursors. The populations are generated by differentiating pluripotent stem cells such as human embryonic stem cells under conditions that promote enrichment of cells with the desired phenotype or functional capability. Various combinations of differentiation factors and mitogens can be used to produce cell populations that are over 95% homogeneous in morphological appearance, and the _expression of oligodendrocyte markers such as GalC. The cells are capable of forming myelin sheaths, and can be used therapeutically improve function of the central nervous system.

App 10/406817 filed April 4, 2003


from Transplant Immunology, Volume 15, Issue 2 , December 2005, Pages 131-142:

Pre-differentiation of hESCs increases the likelihood that the transplant population will survive and maintain their desired phenotype in the host, and decreases the likelihood of teratoma formation. These cells can be driven to yield a high purity population of a desired lineage for a specific cell replacement strategy reducing the influence of environmental signals on the transplant population. Although hESCs may be ideally suited for transplant-mediated remyelination, the environment of human demyelinating pathologies is not. The complex, reactive, and multifocal nature of human demyelinating diseases present significant challenges that must be overcome before cellular replacement strategies become a clinical reality. The more immediately approachable demyelinating pathologies will be those that present relatively fewer environmental challenges, such as spinal cord injury.

from The Journal of Neuroscience, May 11, 2005, 25(19):4694-4705:

Here, we show that transplantation of human embryonic stem cell (hESC)-derived oligodendrocyte progenitor cells (OPCs) into adult rat spinal cord injuries enhances remyelination and promotes improvement of motor function. OPCs were injected 7 d or 10 months after injury. In both cases, transplanted cells survived, redistributed over short distances, and differentiated into oligodendrocytes. Animals that received OPCs 7 d after injury exhibited enhanced remyelination and substantially improved locomotor ability. In contrast, when OPCs were transplanted 10 months after injury, there was no enhanced remyelination or locomotor recovery. These studies document the feasibility of predifferentiating hESCs into functional OPCs and demonstrate their therapeutic potential at early time points after spinal cord injury.

The H7 and H7-enhanced green fluorescent protein (eGFP) hESC lines at passage 32 and the human fibroblast (hFb) line at passage 48 were obtained from Geron (Menlo Park, CA).

Nonetheless, we cannot rule out the possibility that locomotor improvement may have resulted from an uncharacterized effect of the transplant, such as neurotrophin-induced axonal sprouting (Lu et al., 2003 ).


There is an issue about the video shown by "60 Minutes" on February 26, 2006. From
the website of the Reeve-Irvine Center:

Reeve-Irvine Research Center researcher Hans Keirstead was featured in a segment of "60 Minutes" that aired Sunday, Feb. 26. The segment explored Keirstead's efforts to develop a stem cell therapy for spinal cord injury.

The segment featured live video footage of rats; this video was not provided by UCI and is not of Dr. Keirstead's work. The animation featured in the piece - developed and provided by UCI - accurately represented Dr. Keirstead's work.

The Reeve-Irvine Research Center is dedicated to finding treatments for Spinal Cord Injury. We are a research center and currently do not see patients, have a rehabilitation program or run any clinical trials using stem cell or other technologies. Please visit the pages of this web site to learn more about our research programs.


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