More on the bad coverage by Union-Tribune on stem cell matters
In previous posts, we have pointed out that Thomson cited, discussed, and differentiated the work of Bongso in Thomson's '780 patent, a key fact that Somers did not relay to readers.
There is something else that Somers did not mention in her article --Embryonic stem cell pioneer chose to publish, not patent--. In her text, Somers DID mention Jeanne Loring:
“Bongso made the connection between his area of expertise, human embryology, and stem cells, and just went for it,” said Jeanne Loring, a stem cell researcher at the Burnham Institute for Medical Research in La Jolla. “That's how great scientific discoveries are made, for the sake of curiosity.”
(...)
Loring and two nonprofit groups, the Foundation for Taxpayer and Consumer Rights in Santa Monica and the New York-based Public Patent Foundation, had filed a challenge of the Thomson patent in July.
(...)
The lack of interest in human embryonic stem cells was a result of several things, primarily the fact that scientists were immersed in mouse embryonic stem cells, said Loring, from the Burnham Institute.
However, Terri Somers FAILED TO MENTION a published patent application of Loring, US 20020188963 (based on patent application 10/165765, filed June 6, 2002), which includes a claim:
An isolated population of non-mouse embryonic stem cells.
BUT DOES NOT MENTION Bongso, Williams, Hogan, or Thomson within the published specification.
Of relevance to claims by Loring that the "recipe" for isolating and maintaining human stem cells was well-known based on prior work with mouse cells, note paragraph 82 of the published application:
A critical step in deriving embryonic stem cells is culturing the embryo tissue in the presence of pluripotent embryonic stem cells. Without being bound by one theory, it seems that the co-culture method is effective because of cell contact between ES cells and because of self-conditioning of the culture medium by ES cells. The present inventor noted that purified growth factors are not sufficient to provide optimal maintenance of pluripotence and proliferation of undifferentiated ES cells. For mouse ES cells to have a high probability of germ line transmission, mouse ES cells must be cultured on feeder layers, with serum. Most importantly, the inventor also noted that mouse ES cells differentiate much more easily and often when they were cultured at low density rather than high density. These observations led the present inventor to the claimed co-culturing methods.
Paragraph 49 had stated: The present invention provides pluripotent embryonic stem (ES) cells. The ES cells are typically not mouse and, although isolated rat ES cells are exemplified herein, the claimed methods can be applied to any species. In general, the invention provides substantially purified populations of non-mouse, for example rat, ES cells. The methods of producing ES cells involve co-culturing embryo cells from a target species (e.g., inner cell masses (ICMs) from blastocysts or primordial germ cells (PGCs)) with non-target ES cells. The non-target ES cells can be from any species, for instance mouse. Preferably, the non-target ES cells contain a negative selection marker.
***
See also
"More Criticism of the Article by Terri Somers"
Note that a post on californiastemcellreport does not begin to get into the problem with Somers' article. To defeat Thomson's patents, Loring, PubPat, and FTCR bring up prior work, including that of Williams, Hogan, and Bongso (note Bongso was discussed by FTCR and Loring, but was NOT cited by them as art in the re-exam), in a manner very similar to how Glenn Curtiss used Langley against the Wright Brothers. But, when Loring was trying to get her own patent, she did NOT mention Williams, Hogan, and Bongso in HER specification, and did not consider that prior recipes rendered her claim "obvious."
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