Ex Parte Yu et al

Board of Patent Appeals and Interferences

Jan 26, 2012

11527134 (B.P.A.I. Jan. 26, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________

Ex parte LEI YU, KENJI MATSUMOTO,
SHOUPING JI, and FUSHENG DU
__________

Appeal 2010-009987
Application 11/527,134
Technology Center 1600
__________

Before DONALD E. ADAMS, LORA M. GREEN, and
JEFFREY N. FREDMAN, Administrative Patent Judges.

GREEN, Administrative Patent Judge.

DECISION ON APPEAL
This is a decision on appeal under 35 U.S.C. § 134 from the
Examiner’s rejection of claims 1, 2, 5, 7, 8, 11-21, 23-33, 39-42, 45, 46, 49-
52, and 55. We have jurisdiction under 35 U.S.C. § 6(b).
Appeal 2010-009987
Application 11/527,134

2
STATEMENT OF THE CASE
Claim 33 is representative of the claims on appeal, and reads as
follows:
33. A substrate for receiving both nucleic acid and eukaryotic cells, the
substrate consisting of:
a support, the support being coated only with a mixture that consists
of polyethylenimine (PEI) and a biocompatible biopolymer, or a mixture of
PEI, a transferrin-linked PEI, and a biocompatible biopolymer,
wherein the substrate is free of nucleic acid of interest and the PEI
captures, and thereby facilitates adhesion onto the substrate, both nucleic
acid and eukaryotic cells in a solution.

The following ground of rejection is before us for review:
Claims 1, 2, 5, 7, 8, 11-21, 23-33, 39-42, 45, 46, 49-52, and 55
1
stand
rejected under 35 U.S.C. § 103(a) as being rendered obvious by the
combination of Zheng
2
and Kircheis.
3

We reverse.
ANALYSIS
Appellants argue that the use of the transition term “consisting of”
excludes the use of the bifunctional reagent, BS3, used by Zheng, and thus
Zheng teaches away from the claimed invention (App. Br. 11).

1
The Examiner’s statement of the rejection includes claims 22, 53, and 54
(Ans. 4). Claims 53 and 54 were canceled in an after final amendment dated
July 7, 2009 (App. Br. 4), and claim 22 was cancelled in a second after final
amendment dated August 18, 2009 (id. at 5).
2
Zheng et al., Transfection of Cells Mediated by Biodegradable Polymer
Materials with Surface-Bound Polyethyleneimine, 16 BIOTECHNOL. PROG.
254-257 (2000).
3
Kircheis et al., Coupling of cell-binding ligands to polyethylenimine for
targeted gene delivery, 4 GENE THERAPY 409-418 (1997).
Appeal 2010-009987
Application 11/527,134

3
According to the Examiner, the “instant disclosure teaches using PEI
cross-linked with diverse linkers (see paragraphs 0070-0073),” and thus “the
presence of covalent bonds is encompassed by the instant claims” (Ans. 8).
That is, according to the Examiner, “the instant claims do not exclude the
presence of cross-linking agents” (id.). Thus, the issue on appeal is whether
the substrate of Zheng, in which the PEI is cross-linked to the poly (ε-CBZ-
L-lysine), meets the limitation of a substrate consisting of a support being
coated only with a mixture that consists of polyethylenimine (PEI) and a
biocompatible biopolymer, or a mixture of PEI, a transferrin-linked PEI, and
a biocompatible biopolymer.
The Specification teaches preparation of transfection agents using
different linkers, the structures of which are shown in Figure 35 of the
disclosure (Spec. ¶70). The transfection reagents were diluted in a gelatin
solution, which was then added to the wells of a 96 well plate, and the plate
was allowed to air dry (id. at ¶¶ 72-73). Thus, as taught by the
Specification, the cross-linkers were used in the preparation of the
transfection reagents, and not in cross-linking the PEI transfection reagent to
the biocompatible polymer, i.e., the gelatin.
In the statement of the rejection, the Examiner finds that Zheng
teaches “a substrate for receiving both nucleic acids and mammalian cells,
the substrate comprising films made of a mixture between of PEI (i.e.,
cationic polymer) and poly (ε-CBZ-L-lysine) (i.e., a biocompatible
polymer)” (Ans. 4).
Zheng prepares films from poly (ε-CBZ-L-lysine) (PCBZL) and
exposes the amino groups by removal of the CBZ group (Zheng, p. 254,
Appeal 2010-009987
Application 11/527,134

4
second column). PEI was then covalently bound to the films using the
bifunctional reagent BS3 (id. at 255, first column).
Thus, we agree with Appellants that Zheng does not meet the
limitation of a substrate consisting of a support being coated only with a
mixture that consists of polyethylenimine (PEI) and a biocompatible
biopolymer, or a mixture of PEI, a transferrin-linked PEI, and a
biocompatible biopolymer. Specifically, Zheng does not teach a mixture
that consists of polyethylenimine (PEI) and a biocompatible biopolymer, or
a mixture of PEI, a transferrin-linked PEI, but rather teaches crosslinking
PEI to a film comprising a biocompatible polymer, i.e., the poly (ε-CBZ-L-
lysine). As all the pending claims depend on claim 33 (claims 39-42 and
45), require the substrate of claim 33 (claims 1, 2, 5, 7, 8, 11-21, 23-32, 46,
and 49-51), or contain the “consists of” language (claims 52 and 55), we are
compelled to reverse the rejection of claims 1, 2, 5, 7, 8, 11-21, 23-33, 39-
42, 45, 46, 49-52, and 55 under 35 U.S.C. § 103(a) as being rendered
obvious by the combination of Zheng and Kircheis.

REVERSED

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