Appeal No. 1995-1977
Application 07/669,403
cells via Appellants’ method and not the result of being ungulate embryonic stem
cells per se. The record evidence does not support Appellants’ conclusion that
any cell not sharing the four recited characteristics is not an ungulate embryonic
stem cell.
In addition, even if Applicants’ properties were accepted as being
definitive of ungulate embryonic stem cells, at least one cell line disclosed in the
prior art appears to fit the bill. Piedrahita discloses an ungulate embryonic cell
line P3. This cell line is disclosed to “survive[] to the tenth and subsequent
passages,” satisfying Appellants’ third criterion. The cell line also gives rise to
“round cells with large nuclei and prominent nucleoli[,] . . . resembling mouse
teratocarcinoma stem cell colonies.” All of these features are shared by
Appellants’ stem cells, and therefore the P3 cell line appears to satisfy
Appellants’ first criterion of differing from the morphology of murine embryonic
stem cells. Although Piedrahita does not disclose whether the P3 cell line was
fast-growing or slow-growing, nor what types of cells the P3 cell line gave rise to,
all of the disclosed properties of the P3 cell line are consistent with the P3 cells
being ungulate embryonic stem cells, according to Appellants’ own definition.
Appellants also argue that later publications by Piedrahita—his Ph.D.
thesis and a published research article—show that Piedrahita himself concluded
that the cells isolated in the relied-upon reference were not truly embryonic stem
cells. Specifically, Appellants argue that Piedrahita noted in his thesis that “the
term embryonic stem-like (ES-like) is used to distinguish embryo-derived cells
based on morphology; it is not used to imply that the cell line has pluripotential
capabilities.”3 Appeal Brief, page 10.
3 Appellants rely on the Piedrahita thesis and the examiner states that the “Piedrahita Dissertation
. . . was carefully considered.” Examiner’s Answer, page 8. However, the Piedrahita thesis was
7
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Next
Last modified: November 3, 2007