Warren L. Dinges

Patent Trials and Appeals Board

May 12, 2020

2018008464 (P.T.A.B. May. 12, 2020)

UNITED STATES PATENT AND TRADEMARK OFFICE
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.
13/800,495 03/13/2013 Warren L. Dinges CYTO-001/01US
316241-2003
7869
58249 7590 05/12/2020
COOLEY LLP
ATTN: IP Docketing Department
1299 Pennsylvania Avenue, NW
Suite 700
Washington, DC 20004
EXAMINER
BELEI, CARMENCITA
ART UNIT PAPER NUMBER
1641
NOTIFICATION DATE DELIVERY MODE
05/12/2020 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
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PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte WARREN L. DINGES
Appeal 2018-0084641
Application 13/800,495
Technology Center 1600
Before ELIZABETH A. LAVIER, RACHEL H. TOWNSEND, and
CYNTHIA M. HARDMAN, Administrative Patent Judges.
HARDMAN, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134(a) involving claims related to
a method of isolating a target from a sample, comprising forming a mixture
comprising the sample, an antibody-linked immune-sedimentation agent,
and red blood cells. The Examiner rejected the claims as anticipated under
35 U.S.C. § 102(b), and as obvious under 35 U.S.C. § 103(a). We have
jurisdiction under 35 U.S.C. § 6(b).
We affirm.

1 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R.
§ 1.42. Appellant identifies the real party in interest as CytoSed Inc. Br. 3.
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CLAIMED SUBJECT MATTER
The claims are directed to a method of isolating a target from a
sample using an antibody-linked immuno-sedimentation agent (“ALISA”).
Claims 1–3, 6–10, 12–15, 19, 21–29, 32, 34–39 and 66 are on appeal.
See Final Act. 2. Claim 1, reproduced below, is illustrative of the claimed
subject matter:
1. A method of isolating a target from a sample, the method
comprising:
a) forming a mixture comprising the sample, an
antibody-linked immuno-sedimentation agent and red blood
cells, wherein the sample comprises a target and an unwanted
component, wherein the unwanted component comprises an
antigen, and wherein the antibody-linked immuno-
sedimentation agent comprises
1) at least one sedimentation agent that is capable
of inducing red blood cell rouleaux formation and
2) at least one antibody linked to the at least one
sedimentation agent by a non-antigen binding region of the
antibody, wherein the antibody binds to the antigen;
b) incubating the mixture under conditions sufficient to
form a rouleaux and allow the antibody to bind to the antigen
present in the mixture, thus forming a complex comprising the
rouleaux, the antibody-linked immuno-sedimentation agent, and
the unwanted component;
c) separating the complex from the mixture; and
d) recovering the target from the mixture following step
(c), thereby isolating the target from the sample.
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REFERENCES
The references relied upon by the Examiner are:
Name Reference Date
Van Vlasselaer US 5,840,502 Nov. 24, 1998
Kass EP 0696933 B1 July 17, 2002
Collins WO 2002/083262 A1 Oct. 24, 2002
Frank WO 2006/094810 A2 Sept. 14, 2006
REJECTIONS
Claims 1–3, 6–10, 12–15, 22–29, 32, 34–35, 37–39, and 66 stand
rejected under 35 U.S.C. § 102(b) as anticipated by Collins. Final Act. 10.
Claims 1–3, 6–10, 12–15, 19, 21–29, 32, 34–39, and 66 stand rejected
under 35 U.S.C. § 103(a) as obvious over Collins, Van Vlasselaer, Frank,
and Kass.2 Final Act. 14.
OPINION
Appellant argues the claims together. See generally Br.3 We treat
claim 1 as representative of the claims on appeal. Because Appellant did not
separately argue the dependent claims, they stand or fall with claim 1. 37
C.F.R. § 41.37(c)(1)(iv).

2 Although the Examiner listed claims 5 and 30 as subject to the obviousness
rejection (see Final Act. 14, Ans. 6), this appears to be an error, because
claims 5 and 30 are not on appeal. See Final Act. 2; Br. 1.
3 More specifically, Appellant refers to “[i]ndependent claim 1” and
“[i]ndependent claim 9,” and addresses them together. See Br. 5. Because
claim 9 is not independent, we presume Appellant meant to refer to claim
39, which is the only other independent claim on appeal. See Br. 23. In any
event, claim 1 is representative of the claimed subject matter.
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Anticipation
The Examiner found that Collins teaches a method of isolating a
target, e.g., certain cell types, comprising (a) forming a mixture of a blood
sample, an immune sedimentation agent such as dextran, and an antibody
(e.g., an anti-CD4 antibody) linked to a polysaccharide (e.g., dextran); (b)
incubating the mixture under conditions sufficient to form a rouleaux and a
complex comprising the rouleaux, the ALISA, and an unwanted component;
(c) separating the complex from the mixture; and (d) recovering a target
from the mixture following step (c). Final Act. 10–11. The Examiner found
that Collins discloses that dextran can cause rouleaux formation, thus
reading on the claim limitation directed to “at least one sedimentation agent
that is capable of inducing red blood cell rouleaux formation,” which is
recited in step (a)(1) of both independent claims 1 and 39. Id.
We adopt the Examiner’s findings of fact (see, e.g., Final Act. 10–13;
Ans. 3–5, 7–10), and agree that Collins anticipates independent claims 1 and
39. We address Appellant’s arguments below.
Appellant argues that Collins fails to disclose a method that includes
claimed step (b), which recites in relevant part: “forming a complex
comprising the rouleaux, the antibody-linked immune-sedimentation agent,
and the unwanted component.” Br. 6; see also id. at 8. Specifically,
Appellant argues that Collins describes using free dextran and free
antibodies (id. at 8), and “never discloses linking a sedimentation agent to
the antibody.” Id. at 9. Appellant argues that “[s]ince the methods
described by Collins et al. do not involve the use of an ALISA, they
necessarily cannot result in the formation of a complex comprising the
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rouleaux, the ALISA, and the unwanted component, as recited in step (b) of
the instant claims.” Id. at 8.
We are not persuaded by Appellant’s arguments because we disagree
that Collins fails to teach methods using an ALISA. Collins teaches that the
antibodies used in its method “can be bound to substrates such as . . .
polysaccharides.” Collins 3. Collins also teaches that “[d]extran is a
polysaccharide,” and that it “can cause stacking of erythrocytes (i.e., rouleau
formation) and thereby facilitate the removal of erythroid cells from
solution.” Id. at 4. Collins further teaches that “[i]n some embodiments, an
antibody is covalently linked to a polysaccharide such as high molecular
weight (e.g., >1,000,000 Mr) dextran sulfate.” Id. at 7–8. Collins also
teaches that in one embodiment involving use of anti-glycophorin A
antibodies and dextran, the antibodies can facilitate the removal of red blood
cells from solution by “stabiliz[ing] dextran-mediated Rouleau formation.”
Id. at 4. Thus, we find that together, these teachings of Collins adequately
disclose binding an antibody to dextran, i.e., forming an ALISA, where the
dextran is “capable of inducing red blood cell rouleaux formation,” as
recited in claims 1 and 39.
Appellant acknowledges Collins’ teaching that the antibodies can be
bound to a substrate, but argues that “it is very clear from the specification
that the substrates referred to are particulates to facilitate capture and
removal of antibody-bound cells via traditional mean[s],” e.g., using the
mass of the particles to contribute to agglutination and cell separation. Br. 6;
see also id. at 7 (arguing that Collins “indicates that the antibodies facilitate
the removal of targeted blood cells via agglutination,” which is “well known
in the art to be a process distinct from red blood cell rouleaux formation”).
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Appellant argues that “[i]t is abundantly clear that the substrates
contemplated by Collins et al. do not include sedimentation agents capable
of inducing red blood cell rouleaux formation.” Id. at 6. Appellant further
argues that “when Collins et al. discloses an antibody covalently linked to a
polysaccharide such as high molecular weight (e.g., >1,000,000 Mr) dextran
sulfate (page 8, lines 1–2), it is clear that this is to facilitate purification
based on the mass of the high molecular weight dextran sulfate particles and
not via rouleaux formation.” Id. at 9.
We are not persuaded by Appellant’s arguments. Again, Collins
specifically teaches that dextran can be used as an antibody substrate, and
additionally teaches that dextran can form rouleaux, which is one
mechanism that facilitates separation. Collins 4. Further, on this record,
Appellant has not pointed to any evidence demonstrating that high molecular
weight (e.g., >1,000,000 Mr) dextran sulfate would not form rouleaux. See,
e.g., Final Act. 12 (“[W]ith regards to the implication that dextran sulfate of
a high molecular weight is not capable of inducing red blood cell rouleaux
formation, attorney statements which are not evidence must be supported by
an appropriate affidavit or declaration.”); see also Johnston v. IVAC Corp.,
885 F.2d 1574, 1581 (Fed. Cir. 1989) (explaining that attorney argument is
“no substitute for evidence”). We also agree with the Examiner that neither
the intrinsic nor extrinsic evidence supports Appellant’s suggestion that high
molecular weight dextran sulfate would not form rouleaux. Specifically, the
appealed claims simply recite “dextran,” and Appellant’s Specification “is
devoid of any definition of the genus dextran[,] and further discloses the
sedimentation agent as soluble, semi-soluble or insoluble [0040] thus not
excluding for example any dextran sulfate.” Final Act. 12. Additionally,
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Kass specifically identifies high molecular weight dextran as an agent that
aggregates red blood cells into rouleaux. See Kass ¶¶ 3, 4, 15.
Appellant further argues that none of the examples in Collins uses an
ALISA, and that “[i]n each case, the antibody is NOT linked to an
immunosedimentation agent,” and dextran is included in free form. Br. 6, 8.
We are not persuaded by these arguments, because “a reference is not
limited to the disclosure of specific working examples.” In re Mills, 470
F.2d 649, 651 (CCPA 1972). “Patents [and publications] are part of the
literature of the art and are relevant for all they contain.” In re Young, 927
F.2d 588, 591 (Fed. Cir. 1991). As discussed above, Collins expressly
teaches linking dextran and antibodies.
For the above reasons, we affirm the Examiner’s anticipation
rejection.

Obviousness
The Examiner rejected the claims as obvious over the combination of
Collins, Van Vlasselaer, Frank, and Kass. Final Act. 14. The Examiner
relied upon the teachings of Collins as summarized above, and further noted
that Collins does not disclose HES, the elected species of sedimentation
agent.4 Id. The Examiner found that Kass teaches a variety of aggregators
capable of forming rouleaux, including dextran and HES (also known as

4 The Examiner indicated that Appellant elected the species of
hydroxyethylstarch (“HES”) as the sedimentation agent. Final Act. 2, 14,
15–16. As to the § 103 rejection, we limit our analysis to the patentability of
the species addressed by the Examiner, and take no position regarding the
patentability of the broader generic claims. See Ex parte Ohsaka, 2 USPQ2d
1460, 1461 (BPAI 1987).
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“hespan”). Id. The Examiner further found that it would have been obvious
to a skilled artisan to have substituted dextran with HES in the method of
Collins, because dextran and HES were art-recognized equivalents, as taught
by Kass. Id. at 14–15. The Examiner further found that Frank and Van
Vlasselaer teach methods for linking an antibody to polymers such as
dextran. Id. at 15.
We adopt the Examiner’s findings of fact (see, e.g., Final Act. 14–17;
Ans. 5–7, 10–12), and agree that the combination of Collins, Van Vlasselaer,
Frank, and Kass renders obvious independent claims 1 and 39. Indeed, as
discussed above, Collins anticipates these claims, and “anticipation is the
epitome of obviousness.” In re McDaniel, 293 F.3d 1379, 1385 (Fed. Cir.
2002).
Appellant argues that Collins fails to disclose both an antibody-linked
immune-sedimentation agent as claimed, and the step of “forming a complex
comprising the rouleaux, the antibody-linked immune-sedimentation agent,
and the unwanted component,” and that none of the additional cited
references teaches these features. Br. 10–11. For the reasons discussed
above, we disagree that Collins lacks the cited features. We are also not
persuaded by Appellant’s arguments that none of Van Vlasselaer, Frank, or
Kass discloses an ALISA or relates to methods of forming the claimed
complex. The Examiner relied on Collins for disclosing these features, and
as discussed above, we agree with the Examiner that these features are
disclosed in Collins. Appellant cannot show nonobviousness by attacking
references individually as failing to teach all of the claimed limitations
where, as here, the rejection is based on a combination of references, whose
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teachings together render obvious the claimed invention. See In re Keller,
642 F.2d 413, 425 (CCPA 1981).
Appellant further argues that one of skill in the art would not have
been motivated to combine the teachings of Frank with the methods taught
by Collins, because “Frank relates to therapeutic compounds and their use in
treatment, whereas Collins et al. relates to cell separation methods involving
agglutination.” Br. 10–11. We are not persuaded. While we agree with
Appellant that Frank relates to therapeutic compounds, this does not detract
from the relevance of Frank to the Examiner’s rejection. The Examiner
relied on Frank for the limited purpose of demonstrating that methods of
attaching dextran to antibodies were known in the art. Final Act. 15. On
this record, there is no dispute that the methods persons of ordinary skill in
the art would have used for attaching dextran to antibodies were the same
whether the complex was used for therapy as in Frank, or for laboratory use
as in Collins.
Any remaining points of Appellant not specifically addressed above
have been addressed by the Examiner in the Final Action and Answer, and
we adopt the Examiner’s responses as our own.
CONCLUSION
We affirm the rejection of claims 1–3, 6–10, 12–15, 22–29, 32, 34–
35, 37–39, and 66 under 35 U.S.C. § 102(b) as anticipated by Collins.
We affirm the rejection of claims 1–3, 6–10, 12–15, 19, 21–29, 32,
34–39, 66 under 35 U.S.C. § 103(a) as obvious over Collins, Van Vlasselaer,
Frank, and Kass.
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DECISION SUMMARY
Claims
Rejected
35 U.S.C. § Reference(s)  Affirmed Reversed
1–3, 6–10,
12–15, 22–
29, 32, 34–
35, 37–39,
66
102(b) Collins 1–3, 6–10,
12–15, 22–
29, 32, 34–
35, 37–39,
66

1–3, 5–10,
12–15, 19,
21–30, 32,
34–39, 66

103(a) Collins, Van
Vlasselaer, Frank, Kass
1–3, 6–10,
12–15, 19,
21–29, 32,
34–39, 66

Overall
Outcome:
  1–3, 6–10,
12–15, 19,
21–29, 32,
34–39, 66

TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv).
AFFIRMED