Ex Parte Jackson et al

Patent Trial and Appeal Board

Oct 29, 2018

13824307 (P.T.A.B. Oct. 29, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
13/824,307 03/15/2013
29693 7590 10/31/2018
WILEY REIN LLP
1776 K STREET N.W.
WASHINGTON, DC 20006
FIRST NAMED INVENTOR
Graham Stuart Jackson
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
ATTORNEY DOCKET NO. CONFIRMATION NO.
86499.0003\US 6582
EXAMINER
MARCSISIN, ELLEN JEAN
ART UNIT PAPER NUMBER
1641
NOTIFICATION DATE DELIVERY MODE
10/31/2018 ELECTRONIC
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.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
ptodocket@wileyrein.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte GRAHAM STUART JACKSON, JOHN COLLINGE,
and JULIE ANN EDGEWORTH 1
Appeal2017-009582
Application 13/824,307
Technology Center 1600
Before DEMETRA J. MILLS, ERIC B. GRIMES, and
JOHN E. SCHNEIDER, Administrative Patent Judges.
GRIMES, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 involving claims to a method
for detecting abnormal prion protein, which have been rejected as obvious.
We have jurisdiction under 35 U.S.C. § 6(b).
We reverse.
STATEMENT OF THE CASE
"Prion diseases are a group of fatal neurodegenerative disorders
including variant Creutzfeldt-Jakob disease (vCJD)." Spec. 1. "The
infectious agents, or prions, responsible for transmission of disease are
1 Appellants identify the Real Party in Interest as D-Gen Limited. Appeal Br. 1.
Appeal2017-009582
Application 13/824,307
composed principally if not entirely of a misfolded form of the host prion
protein, PrPc .... When recruited during prion propagation PrPc is
remodelled to an aggregated, detergent insoluble isoform designated PrP8c."
Id. at 2. "[T]he invention is concerned with the detection of abnormal PrP or
disease associated PrP .... Most suitably the abnormal PrP may be PrP8c."
Id. at 11.
Claims 1-3, 6, 9-11, 14, 16, and 17 are on appeal. Claim 1 is the only
independent claim and reads as follows:
1. A method for detection of abnormal prion protein (PrP) in a
sample of blood, said method comprising:
(a) diluting the sample in the range of 1:10 to 1:100, inclusive,
with buff er to comprise final concentrations of
(i) lOmM to 500mM buffer agent;
(ii) 1 % to 10% w/v bovine serum albumin; and
(iii) 1 % to 8% w/v 3-[(3-
cholamidopropyl)dimethylammonio ]-1-propanesulfonate
(CHAPS); and
wherein said buffer does not include chaotropic agents or
proteinases;
(b) adding steel particles and incubating to allow PrP binding;
( c) washing the steel particles to remove diluted sample;
( d) heating the steel particles to 110°C for 5 minutes; and
( e) detecting abnormal PrP captured on the steel particles using
antibody or a fragment thereof capable of binding said abnormal PrP;
wherein said method is practiced without use of chaotropic
agents or proteinases.
2
Appeal2017-009582
Application 13/824,307
The claims stand rejected as follows:
Claims 1-3, 6, 9-11, 16, and 17 under 35 U.S.C. § I03(a) as obvious
based on Collinge, 2 Enari, 3 Healy, 4 Tsuji, 5 Green, 6 Aslamkhan, 7 and
Harlow8 (Ans. 2) and
Claim 14 under 35 U.S.C. § I03(a) as obvious based on Collinge,
Enari, Healy, Tsuji, Green, Aslamkhan, Luhr,9 and Goodfellow10 (Ans. 14).
DISCUSSION
The Examiner has rejected all of the claims on appeal as obvious
based on Collinge, Enari, Healy, Tsuji, Green, and Aslamkhan, combined
with either Harlow, or Luhr and Goodfellow. The same issue is dispositive
for both rejections.
The Examiner finds that Collinge teaches a method meeting most of
the limitations of claim 1, but teaches "performing denaturation [ of prion
proteins] using reagent[ s] such as detergent or chaotrope." Ans. 3. The
Examiner also finds that Collinge "does not specifically teach wherein the
solid phase is composed of steel particles, and ... does not specifically teach
2 Collinge et al., WO 2009/040508 A2, published April 2, 2009.
3 Enari et al., US 2008/0108085 Al, published May 8, 2008.
4 Healy et al., US 2006/0030535 Al, published Feb. 9, 2006.
5 Tsuji et al., US 2005/0202400 Al, published Sept. 15, 2005.
6 Green, US 2004/0018554 Al, published Jan. 29, 2004.
7 Aslamkhan et al., US 2003/0044868 Al, published Mar. 6, 2003.
8 Harlow et al., Antibodies A Laboratory Manual, COLD SPRING HARBOR
PRESS pp. 447, 460, 689 (1988.
9 Luhr et al., Prion adsorption to stainless steel is promoted by nickel and
molybdenum, 90 J. GEN. VIROL. 2821-2828 (2009).
10 Goodfellow Cambridge Ltd., Goodfellow Catalog, pp. 80-83 (2009).
3
Appeal2017-009582
Application 13/824,307
heating steel particles to 110°C for 5 minutes .... Collinge et al. also does
not teach wherein the detergent is CHAPS and does not specifically teach
diluting the sample with buffer in the range of 1:10 to 1:100." Id. at 4.
The Examiner finds that Enari teaches a device for detection of PrP8c
in which the PrP8c binds to stainless steel spheres. Id. at 4--5. The Examiner
finds that Healy teaches immunoassay methods "using a range of dilutions
of each sample for analysis, teaching larger dilution factors (1: 100-1: 1000)
as well as dilution factors of 1: 5-1: 10 ... overlapping the ranges as instantly
described." Id. at 5.
The Examiner finds that Tsuji teaches that sodium lauroylsarcosine
( taught by Collinge) and CHAPS are equivalent surfactants for disrupting
cell membranes. Id. The Examiner also finds that Green teaches methods for
detecting prions that include pre-treatment of samples with detergents, such
as CHAPS, to remove bound lipids. Id. at 6. The Examiner finds that
Aslamkhan teaches denaturing PrP8c by heating it for 2-20 minutes. Id. at 7.
Id.
The Examiner concludes that it would have been obvious
to have modified the invention of Collinge et al. to implement
the stainless steel spheres (i.e. particles) of Enari et al. in place
of the solid support beads of Collinge et al. because such a
stainless steel device would advantageously preserve prions
against degradation, and would allow direct binding to the
surface (i.e. eliminate the need for a non-specific protein or
capture antibody).
The Examiner also concludes that it would have been obvious
to perform sample dilutions using dilution factors in the range
of 1: 10 to 1: 100, as described by Healy et al., when performing
the method for the detection of abnormal prion protein in blood,
as taught by the combination of the prior art in order to ensure
4
Appeal2017-009582
Application 13/824,307
that sample concentrations fall within the dynamic range for
assay in order to allow accurate detection and quantitation of
protein
and "dilution is a result effective variable that would be optimized through
routine experimentation." Id. at 8.
The Examiner concludes that it would have been obvious
to substitute the detergent (surfactant) CHAPS, as taught by
Tsuji et al. and Green, for the detergent sodium
lauroylsarconsine [sic], as exemplified by Collinge et al.,
because CHAPS and sodium lauroylsarcosine were recognized
in the prior art to be functional equivalents known for the same
purpose, namely as solubilizing agents for disrupting cellular
membranes
and Green teaches that non-denaturing detergents such as CHAPS are
preferred to remove bound lipids. Id. at 9.
The Examiner concludes that it would have been obvious "to exclude
chaotropic agents from the method of Collinge et al. because Green teaches
it is preferable to rely on non-denaturing agents in order to maintain the
secondary and tertiary structure of the protein, thereby reducing cross-
reactivity of binding moieties." Id. at 10. Finally, the Examiner concludes
that it would have been obvious "to have modified the heat treatment step of
Collinge et al., teaching heating solid phase bound prion to 100°C for 10
minutes, to 110°C for 5 minutes as a matter of routine optimization because
the teachings of Collinge et al. are on the same order of magnitude as the
temperature and time instantly claimed." Id. at 11.
Appellants argue, among other things, that the cited references would
not have made obvious the step of heating prion proteins bound to steel
particles to 110°C for 5 minutes, as recited in the claims on appeal. Appeal
5
Appeal2017-009582
Application 13/824,307
Br. 46. Appellants argue that Collinge boiled its sample in SDS buffer at
100°C for 10 minutes to dissociate prions from bead-bound antibodies, so
that the prions could be detected in the supernatant. Id. Appellants argue that
Aslamkhan teaches heating to 85°C-100°C, "well below the claimed
110°C," and also teaches Proteinase K ("PK") treatment of its sample. Id.
We agree with Appellants that the cited references would not have
made obvious, at least, the step of claim 1 requiring heating prion proteins
bound to steel particles to 110°C for 5 minutes, before detecting abnormal
prion proteins captured on the steel particles.
Collinge discloses binding antibody-bound prion proteins (PrP) to
beads, which were then washed and heated to 100°C for 10 minutes.
Collinge 28:21 to 29:5. "Beads were sedimented by centrifugation at
15,000 x g for 2 min prior to analysis of the supernatant by western
blotting." Id. at 29:5-7 ( emphasis added). Collinge's disclosure therefore
supports Appellants' position that Collinge included a heating step to
dissociate the prions from the beads, whereas claim 1 requires "detecting
abnormal PrP captured on the steel particles," after heating to 110°C for 5
minutes.
Aslamkhan discloses "a method for detecting, in the absence of
guanidine salts and acids, the presence of prion protein in a tissue sample at
ambient pressure comprising: heating said tissue sample to a temperature
effective to denature said prion protein, and detecting said denatured prion
protein." Aslamkhan ,r 6. Aslamkhan states that "[p ]rion is extracted from a
tissue sample and treated with proteinase K .... The protein homogenate or
solution is then heated for between about 2 and 20 minutes ... at a
6
Appeal2017-009582
Application 13/824,307
temperature between 75° C. and about 100° C., more preferably between 80°
C. and about 90° C., most preferably about 85° C." Id. ,r 72.
Thus, both Collinge and Aslamkhan disclose heating a sample to, at
most, 100° C. In Collinge, the heating step dissociates prions from a solid
support (beads), while in Aslamkhan the heating denatures the prions.
However, neither reference suggests that heating to a temperature above
100° C would have any benefit. Thus, the evidence does not support the
Examiner's position that it would have been obvious to a person of ordinary
skill in the art to "modif-1y] the heat treatment step of Collinge et al, teaching
heating solid phase bound prion to 100°C for 10 minutes, to 110°C for 5
minutes as a matter of routine optimization." Ans. 11.
In summary, we reverse both of the rejections on appeal because the
Examiner has not shown that a method meeting all of the limitations of the
claims on appeal would have been obvious to a person of ordinary skill in
the art based on the cited references.
REVERSED
7