Ex Parte Verfaillie et al

Patent Trial and Appeal Board

Dec 6, 2012

10561826 (P.T.A.B. Dec. 6, 2012)

UNITED STATES PATENT AND TRADEMARKOFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
10/561,826 10/17/2006 Catherine M. Verfaillie 89003-2006.1 2871
26294 7590 12/06/2012
TAROLLI, SUNDHEIM, COVELL & TUMMINO L.L.P.
1300 EAST NINTH STREET, SUITE 1700
CLEVELAND, OH 44114
EXAMINER
WANG, CHANG YU
ART UNIT PAPER NUMBER
1649
MAIL DATE DELIVERY MODE
12/06/2012 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
__________

Ex parte CATHERINE M. VERFAILLIE and YUEHUA JIANG
__________

Appeal 2012-001641
Application 10/561,826
Technology Center 1600
__________

Before TONI R. SCHEINER, MELANIE L. McCOLLUM, and
ULRIKE W. JENKS, Administrative Patent Judges.

McCOLLUM, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 involving claims to a method
for inducing cells to differentiate into neuronal cells. The Examiner has
rejected the claims as obvious. We have jurisdiction under 35 U.S.C. § 6(b).
We reverse.
Appeal 2012-001641
Application 10/561,826

2
STATEMENT OF THE CASE
Claims 1, 5, 6, and 13 are on appeal (App. Br. 5).1 We will focus on
independent claims 1 and 13, which read as follows:
1. A method for inducing stem cells to differentiate into neuronal
cells comprising:
a) culturing said stem cells with basic fibroblast growth factor;
b) culturing the cells of step a) with fibroblast growth factor 8 and
Sonic Hedgehog;
c) culturing the cells of step b) with brain-derived neurotrophic factor;
and
d) co-culturing the cells of step c) with astrocytes;
wherein said cells are cultured according to steps a) through d) for at least
seven days at each step.
13. A method for inducing cells to differentiate into neuronal cells
comprising co-culturing the cells with astrocytes, said cells having gone
through the steps of:
a) culturing stem cells with basic fibroblast growth factor;
b) culturing the cells of step a) with fibroblast growth factor 8 and
Sonic Hedgehog; and
c) culturing the cells of step b) with brain-derived neurotrophic factor;
wherein said cells are cultured according to steps a) through c) for at least
seven days at each step.
Claims 1, 5, 6, and 13 stand rejected under 35 U.S.C. § 103(a) as
obvious over Studer2 in view of Lee3 (Ans. 5).
Claims 1, 5, 6, and 13 stand rejected under 35 U.S.C. § 103(a) as
obvious over Studer in view of Lee and Song4 (Ans. 12).

1 According to Appellants, claims 2-4 and 7-12 have been cancelled (App.
Br. 5).
2 Studer et al., WO 02/086073 A2, Oct. 31, 2002.
3 Lee et al., US 2003/0211605 A1, Nov. 13, 2003.
4 Song et al., Preparation of Neural Progenitors from Bone Marrow and
Umbilical Cord Blood, 198 METHODS IN MOL. BIOL. 79-88 (2002).
Appeal 2012-001641
Application 10/561,826

3
I
The Examiner acknowledges that “Studer does not explicitly teach
adding bFGF, FGF8, SHH, BDNF sequentially, does not explicitly teach
co-culturing with astrocytes and does not explicitly teach that cells were
cultured for at least 7 days at each step” (Ans. 7). However, the Examiner
finds:
Although the instant method recites adding bFGF, FGF8, SHH,
BDNF sequentially, at the end of the final steps, the culture
medium contains identical growth factors as those in the
Studer’s method to induce neuronal differentiation. The result
of inducing neuronal differentiation from stem cells by adding
bFGF, FGF8, SHH and BDNF in a different order are expected
(i.e. induction of neuronal differentiation), and do not result in
any unexpected result because at the end of the culture, the
culture medium still contains the same growth factors (bFGF,
FGF8, SHH and BDNF) added in the culture, the same cultured
ES cells, and the cultured ES cells are capable of differentiate
into neurons. Note that the instant invention do not claim a
method to induce differentiation of stem cells into specific
neuronal populations or to induce differentiation of stem cells
into different ratios of specific neuronal cells.
(Id.)
The Examiner also finds that “Studer teaches the differentiation of
cultured embryonic stem cells into neurons and glial cells” and that “the
glial cells encompass astrocytes as supported by Lee” (id. at 8). In addition,
the Examiner finds that “it is obvious to co-culture stem cells that have been
treated with bFGF, FGF8, Shh and BDNF with astrocytes to induce neuronal
differentiation” (id.). The Examiner also finds: “[E]ach step and each stage
of the culture conditions of Studer require 6-9 days and the whole culture
procedures take more than one month. . . . Thus, the culturing steps and
Appeal 2012-001641
Application 10/561,826

4
conditions are within the limitation of the instant claims 1 and 13.” (Id. at
9.) The Examiner concludes that “it would have been obvious to add
different growth factors sequentially . . . because each different growth
factor can increase specific type cell populations and the use of the
combination of the claimed growth factors have been shown to successfully
induce neuronal differentiation from stem cells” (id. at 11).
Findings of Fact
1. Studer discloses a method of generating a neuronal cell
comprising: (I) “culturing a nuclear transfer embryonic stem (ntES) cell in a
first container”; (II) resuspending the cells in a serum-containing medium in
a second container; (III) replacing the medium with “serum free media
supplemented with an attachment factor,” whereby the embryoid body is
allowed to grow such that it “expresses the neural stem cell marker nectin”;
(IV) placing the “embryoid body expressing nectin . . . in a third container
coated with polyornithine/lamininin” and supplementing the medium with a
mitogen, laminin, sonic hedgehog, and FGF8; and (V) withdrawing the
mitogen “from the medium (e.g., the media is replaced with media that does
not contain the mitogen)[, whereby] a differentiated neural cell is formed”
(Studer 4: ¶¶ 12-14; see also 24-25: ¶¶ 74-76 & 26-29: ¶¶ 80-87).
2. Studer also discloses: “In one embodiment the method is
specific for generating a dopaminergic neuron. In a particular embodiment
of this type, the mitogen is bFGF.” (Id. at 4: ¶ 15.)
3. In addition, Studer discloses that “[o]ther factors that can
further promote dopaminergic differentiation of ntES cells at stage IV and/or
Appeal 2012-001641
Application 10/561,826

5
V are factors that affect DA neuron induction and survival such as . . .
BDNF” (id. at 25-26: ¶ 77).
4. Studer also discloses that “[c]ells are typically grown
(proliferated) in stage IV for 6 - 9 days” (id. at 29: ¶ 86).
5. In addition, Studer discloses:
At stage V (differentiation) the medium typically used is N2
medium in the absence of any mitogens such as bFGF or BGF,
but in the presence of ascorbic acid. . . . In addition other
factors such as BDNF . . . and/or other factors promoting
dopaminergic differentiation and survival may be added. After
4 - 10 days large numbers of dopamine neurons can be detected.
(Id. at 29: ¶ 87.)
6. Lee discloses a method of culturing cells including the
following “stages: (1) expansion of ES cells; (2) generation of embryoid
bodies; (3) selection of CNS [central nervous system] precursor cells;
(4) expansion of CNS precursor cells; and (5) differentiation of CNS
precursor cells” (Lee, Abstract & 3: ¶ [0040]).
7. Lee also discloses that, during stage 4, “the CNS precursors are
expanded from about 6 to about 7 days” (id. at 9: ¶ [0123]).
8. In addition, Lee discloses that the “CNS proliferation media
may . . . be supplemented with neurologic agents to encourage
differentiation into neuron cells such as secreted signaling factors.
Preferably, the culture media includes . . . basic fibroblast growth factor
(bFGF).” (Id. at 9: ¶ [0124].)
9. Lee also discloses that the “culture media may also be
supplemented with neurologic agents to increase the efficiency of the
generation of midbrain dopaminergic neurons. . . . Preferably, the media
Appeal 2012-001641
Application 10/561,826

6
includes . . . sonic hedgehog (SHH) protein . . . and . . . fibroblast growth
factor-8 (FGF8).” (Id. at 9: ¶ [0125].)
Analysis
Claim 1 is directed to a method for inducing stem cells to differentiate
into neuronal cells. The method comprises: (a) culturing the stem cells with
basic fibroblast growth factor for at least seven days; culturing the cells
resulting from step (a) with fibroblast growth factor 8 and Sonic Hedgehog
for at least 7 days; (c) culturing the cells resulting from step (b) with brain-
derived neurotrophic factor for at least 7 days; and (d) co-culturing the cells
resulting from step (c) with astrocytes for at least 7 days.
Studer discloses a method of generating a neuronal cell comprising a
stage (stage IV) in which the cells are cultured for 6-9 days with basic
fibroblast growth factor, fibroblast growth factor 8, and Sonic Hedgehog
followed by a stage (stage V) in which the cells are cultured for 4-10 days
with brain-derived neurotrophic factor (Findings of Fact (FF) 1-5).
However, the Examiner does not point to any teaching in Studer of a method
comprising: (a) culturing the stem cells with basic fibroblast growth factor
for at least seven days; followed by (b) culturing the cells resulting from
step (a) with fibroblast growth factor 8 and Sonic Hedgehog for at least 7
days (see Ans. 7 (“Studer does not explicitly teach adding bFGF, FGF8,
SHH, BDNF sequentially”)). It addition, we agree with Appellants that the
Examiner has not set forth a prima facie case that such a method would have
been obvious.
We note initially that the Examiner does not rely on Lee to overcome
this deficiency. On the contrary, the Examiner finds that “Lee teaches that
App
App

the C
in th
med
FF 6
claim
expl
obvi
inste
unde
441
set fo
the c
Br. 1
to co
a sta
with
surv
pend

5 Wa
astro
(Abs
6 We
eal 2012-0
lication 10
NS precu
e presence
ium may a
-9).
In additi
1, we ag
ained why
ousness gr
ad, there m
rpinning t
F.3d 977,
We also
rth a prim
ells resulti
4). We no
-culture th
ndard proc
astrocytes
ival as evid
ing rejecti

lsh et al., N
cytes co-c
tract only)
iss et al., U
01641
/561,826
rsor cells .
of bFGF
lso be sup
on, in the
ree with A
this seque
ounds can
ust be som
o support t
988 (Fed.
agree with
a facie ca
ng from st
te the Exa
e cells wit
edure to c
or an astr
enced by
on concern

euronal s
ultured in
.
S 5,851,8
. . are exp
or EGF for
plemented
absence of
ppellants t
nce would
not be sus
e articula
he legal co
Cir. 2006)
Appellan
se that Stu
ep (c) with
miner’s re
h astrocyt
ulture neu
ocyte feed
Walsh5” a
s whether

urvival an
transwells
32, Dec. 2
7
anded in t
about 6 to
with SHH
any teach
hat the Ex
have been
tained by m
ted reason
nclusion
.
ts’ argume
der and Le
astrocyte
sponse tha
es because
ronal prog
er layer to
nd Weiss6
the claim
d neurite
, 138 NEU
2, 1998.
he CNS pr
7 days” a
and FGF
ing of the
aminer ha
obvious.
ere concl
ing with s
of obvious
nt that the
e teach or
s for at le
t it would
“it is kno
enitor cell
maintain
(Ans. 17 &
s are obvio
extension
ROSCI LET
oliferation
nd “that t
8” (Ans. 1
sequence
s not adeq
“[R]eject
usory stat
ome ratio
ness.” In
Examine
suggest co
ast 7 days
have been
wn in the
s or neural
or enhance
8). How
us over S
supported
T. 103-6 (
medium
he culture
0; see also
recited in
uately
ions on
ements;
nal
re Kahn,
r has not
-culturing
(App.
obvious
art and it i
stem cell
neuronal
ever, the
tuder and
by
1992)

s
s
Appeal 2012-001641
Application 10/561,826

8
Lee not whether the claims are obvious over Studer and Lee in view of
Walsh and Weiss. We therefore find this response inadequate.7
For the forgoing reasons, we agree with Appellants that the Examiner
has not set forth a prima facie case that claim 1 would have been obvious
over Studer and Lee. We therefore reverse the obviousness rejection over
Studer and Lee of claim 1 and of claims 5 and 6, which depend from
claim 1.
Claim 13, however, stands on somewhat of a different footing. We
note initially that claim 13 does not require co-culturing the cells with
astrocytes for at least 7 days. Thus, we are not persuaded by Appellants’
argument that, “even if one assumes . . . that [Studer’s] glial cells are
astrocytes, there is no teaching that any cell is incubated with an astrocyte
for the seven day time period” (App. Br. 14).
In addition, we interpret steps (a)-(c) of claim 13 to be product-by-
process limitations. However, given that the Examiner has not set forth a
prima facie case that the methods disclosed in Studer and/or Lee would
provide the same cells as the method of steps (a)-(c), we conclude that the

7 We recognize that it can be proper to rely on a reference as evidence that,
for example, an applied reference inherently teaches a claim feature. Here,
however, the Examiner appears to be relying on Walsh and Weiss as
“evidence” that it would have been obvious to modify the methods of Studer
and Lee to include the co-culturing step. We do not agree that this is a
proper use of “evidence” references. Instead, if these references are needed
to support a prima facie case of obviousness, they should be included in a
rejection. See In re Hoch, 428 F.2d 1341, 1342 n.3 (CCPA 1970) (“Where a
reference is relied on to support a rejection, . . . there would appear to be no
excuse for not positively including the reference in the statement of
rejection.”).
Appeal 2012-001641
Application 10/561,826

9
Examiner has not set forth a prima facie case that the method of claim 13
would have been obvious over Studer and Lee. We therefore also reverse
the obviousness rejection of claim 13 over Studer and Lee.
II
In the second rejection, the Examiner additionally relies on Song for
teaching “differentiation of stem cells derived from different multipotent
adult progenitor cells (MAPCs) and bone marrow” (Ans. 13). The Examiner
concludes that it would have been obvious “to differentiate stem cells that
are derived from multipotent adult progenitor cells (MAPCs) and bone
marrow into neurons by using the culture conditions of Studer and Lee”
(id.). However, the Examiner does not set forth a prima facie case that Song
cures the above-mentioned deficiencies of Studer and Lee. We therefore
reverse the rejection of claims 1, 5, 6, and 13 over Studer, Lee, and Song.

REVERSED

dm