Indee. Inc.

Patent Trials and Appeals Board

Sep 27, 2021

2021005157 (P.T.A.B. Sep. 27, 2021)

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.
15/497,122 04/25/2017 Ryan Pawell IND3-002-010US 3987
127866 7590 09/27/2021
Southern Cross Intellectual Property
PO Box 906
Brisbane QLD, 4001
AUSTRALIA
EXAMINER
POPA, ILEANA
ART UNIT PAPER NUMBER
1633
NOTIFICATION DATE DELIVERY MODE
09/27/2021 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):
docketing@martinip.com
tmartin@martinip.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
__________

Ex parte RYAN PAWELL
__________

Appeal 2021-005157
Application 15/497,122
Technology Center 1600
__________

Before JEFFREY N. FREDMAN, CYNTHIA M. HARDMAN, and
JAMIE T. WISZ, Administrative Patent Judges.

FREDMAN, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal1 under 35 U.S.C. § 134 involving claims to a method
for introducing an exogenous material into a cell. The Examiner rejected the
claims as obvious. We have jurisdiction under 35 U.S.C. § 6(b). We
reverse.

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 lndee. Inc.
(see Appeal Br. 2). We have considered the Specification of April 25, 2017
(“Spec.”); Final Office Action of Nov. 19, 2020 (“Final Action”); Appeal
Brief of Jan. 13, 2021 (“Appeal Br.”); Examiner’s Answer of June 29, 2021
(“Ans.”); and Reply Brief of Aug. 26, 2021 (“Reply Br.”).
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Statement of the Case
Background
“[T]he ability to introduce exogenous material and in particular
nucleic acids into cells in a quick and efficient manner is both a valuable
research tool and a useful component of a therapeutic strategy” (Spec. ¶ 7).
“[T]he introduction of agents such as nucleic acids into eukaryotic cells is
generally referred to as ‘transfection’, whereas the introduction of nucleic
acid into prokaryotic cells is generally referred to as ‘transformation’.
Transfection and transformation methods may be conveniently separated
into three categories, namely, chemical, physical and viral-based methods”
(id. ¶ 9).
The Specification teaches “[i]t has been surprisingly found by the
inventor that, when exposed to a transient decrease in pressure, cells are
susceptible to the uptake of exogenous material” (Spec. ¶ 18). “A relatively
sudden and temporary pressure drop across the cell membrane, whereby the
intracellular pressure is greater than the extracellular pressure, may result in
the temporary formation of pores in the membrane allowing for the
introduction of the exogenous material” (id. ¶ 19).
The Claims
Claims 1, 2, 4–7, 17, and 21–43 are on appeal. Claim 1 is an
independent claim, is representative and reads as follows:
1. A method for introducing an exogenous material into a
cell, comprising:
introducing a liquid including the cell and the exogenous
material into a flow channel of a microfluidic device, the
channel including at least two flow diverters, the gap between
the at least two flow diverters having a width, the width of the
gap being greater than the diameter of the cell; and
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exposing said cell to a transient decrease in pressure and
unsteady flow downstream of the flow diverters when the cell
flows past the flow diverters to thereby introduce said
exogenous material into said cell.

The Rejections
A. The Examiner rejected claims 1, 2, 4–7, 17, 22–33, and 36–43 under
35 U.S.C. § 103(a) as obvious over Sharei,2 Clarke,3 Doranz,4 and Hans5
(Final Act. 2–5).
B. The Examiner rejected claims 1, 2, 4–7, 17, 21–33, and 36–43 under
35 U.S.C. § 103(a) as obvious over Sharei, Clarke, Doranz, Hans, and
Diefenbach6 (Final Act. 5–6).
C. The Examiner rejected claims 1, 2, 4–7, 17, and 22–43 under 35
U.S.C. § 103(a) as obvious over Sharei, Clarke, Doranz, Hans, and Hejna7
(Final Act. 6–7).
A. 35 U.S.C. § 103(a) over Sharei, Clarke, Doranz, and Hans
The Examiner finds Sharei teaches
a microfluidic method for the intracellular delivery of an
exogenous macromolecule, the method comprising passing a
fluid comprising cells and the macromolecule to be delivered

2 Sharei et al., A vector-free microfluidic platform for intracellular delivery,
110 Proc. Nat’l Acad. Sci. USA 2082–87 (2013).
3 Clarke et al., US 8,529,026 B2, issued Sept. 10, 2013
4 Doranz et al., US 2005/0123563 A1, published June 9, 2005.
5 Hans et al., Comparison of pressure and ultrasound measurements in
vortex flow meters, 33 Measurement 121–33 (2003).
6 Diefenbach, T., US 2012/0064518 A1, published Mar. 15, 2012.
7 Hejna et al., Functional complementation by electroporation of human
BACs into mammalian fibroblast cells, 26 Nucleic Acids Res. 1124–5
(1998).
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through an enclosed microchannel comprising at least one
constriction (i.e., obstacle) having a dimension smaller than the
cell diameter to induce transient holes into the cell membrane
and introduce the macromolecule and siRNAs into the cell
cytoplasm.
(Final Act. 3). The Examiner acknowledges that Sharei does “not
specifically teach unsteady flow around the flow diverter, nor do they teach
a transitional vortex street” (id.).
The Examiner finds “modifying the method of Sharei [] by using
obstacles resulting in a vortex street is suggested by the prior art” because
Clarke teaches “bluff bodies or pillars (such as cylinders) placed within a
microchannel could be used to create unsteady flow such (as a vortex street)
in the microchannel” and Doranz teaches “vortices can be used to create
transient holes in lipid membranes” (Final Act. 3). The Examiner finds
Hans evidences that “vortex structures are areas of lower pressure than the
surrounding liquid” (id. at 3–4).
The Examiner finds it obvious to combine “to achieve the predictable
result of introducing macromolecules into cells by creating transient holes
into the cell membrane via a vortex street. By doing so, one of skill in the
art would have used a microfluidic device comprising at least two flow
diverters separated by gaps” (Final Act. 4). The Examiner finds the ordinary
artisan “would have concluded that a gap with a dimension smaller than the
cell diameter is not necessary when using a vortex and would have found
obvious to use a gap width greater than the cell diameter” (id.).
Appellant contends “that for a case involving method claims,
motivation is required” (Appeal Br. 8). Appellant specifically contends:
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Sharei teaches that a constriction smaller than the cell diameter
is necessary to induce transient holes into the cell membrane.
Attempting to modify Sharei so that it is actually opposite to
what Sharei says is necessary is prima facie hindsight reasoning
. . . Additionally, the device of Sharei is optimized for
eliminating vortices (Sharei at page 2083, column 1), so
attempting to modify the Sharei device and method so that it
produces vortices is contrary to one of the key principles
underlying Sharei’s design.
(id. at 5). Appellant contends “the inkjet technology of Clarke would not
have logically commended itself to an inventor’s attention in considering the
problem” (id. at 11). Appellant also “disagrees that either Doranz or Clarke
alone or together make up for the deficiencies of Sharei, or that it would
have been obvious to one skilled in the art to combine these references” (id.
at 6). Appellant contends the “circular airflow behind the bluff bodies of
Hans are not equivalent to Appellant’s transient decrease in pressure and
unsteady flow” (id. at 7). Lastly, Appellant contends that “[w]hen fully and
properly considered, the claimed invention shows surprising results, as
evidenced by the Di Carlo Declaration” (id. at 12).
The issues with respect to this rejection are:
(i) Does a preponderance of the evidence of record support the
Examiner’s conclusion that the prior art suggests the method of claim 1?
(ii) If so, has Appellant provided evidence of unexpected results that
outweighs the evidence supporting the prima facie case of obviousness?
Findings of Fact
1. Sharei teaches methods “for cytosolic delivery based on rapid
mechanical deformation of the cell to produce transient membrane
disruptions that facilitate the passive diffusion of material into the cell
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cytosol. This method was developed with the aim of delivering almost any
macromolecule of interest to almost any cell type, at high throughput”
(Sharei 2082, col. 2).
2. Figure 1, panels A and B of Sharei are reproduced below:

Fig. 1. Delivery mechanism and system design. (A) Illustration
of delivery hypothesis whereby the rapid deformation of a cell,
as it passes through a microfluidic constriction, generates
transient membrane holes. Includes an electron micrograph of
current parallel channel design with blue cells as an illustration.
(B) Image of a finished device consisting of Pyrex bound to
silicon for sealing.
(Sharei 5283, col. 1).
3. Sharei teaches “the rapid mechanical deformation of a cell, as it
passes through a constriction with a minimum dimension smaller than the
cell diameter, results in the formation of transient membrane disruptions or
holes” (Sharei 2082, col. 2).
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4. Sharei teaches:
We identified cell speed, constriction dimensions, and number
of constrictions as three parameters that influence delivery
efficiency (defined as the fraction of live cells that receive the
delivery material []) by altering the shear and compression rates
experienced by the cells. For example, delivery efficiency of
membrane-impermeable, Cascade Blue-labeled 3-kDa dextran
molecules to live HeLa cells increases monotonically with cell
speed across different constriction designs . . . Constriction
dimensions also impact delivery; increasing the constriction
length from 20 to 40 μm almost doubled delivery efficiency at
all operating speeds . . . with minimal effect on viability . . .
Decreasing constriction width had a similar effect . . .
Increasing the number of constrictions in series also increased
delivery efficiency such that a device with five 10-μm length
constrictions in series outperformed a single 10-, 20-, or 40-μm
length design across all cell speeds.
(Sharei 2083, col. 2).
5. Clarke teaches “a device and method for generating droplets of
a fluid in a controlled manner with a low range of size dispersity at a rate
sufficient for practical commercial use” (Clarke 2:57–60).
6. Clarke teaches
flow instability may be caused, for example, by the creation of
a series of unsteady eddies within the channel. Preferably, the
flow instability is caused by the shedding, preferably periodic
or regular, of vortices. Most preferably the flow instability is
due to a vortex street in the droplet fluid in the channel.
(Clarke 5:38–43).
7. Clarke teaches “perturbation means may include bluff bodies
placed within a channel of constant cross-section or it may include changes
to the geometry of the channel cross-section, for example constrictions,
corners or junctions” (Clarke 6:5–9).
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8. Doranz teaches: “Temporary poration or permeabilization can
be achieved by such treatments as electroporation, exposure to chemicals or
proteins (e.g. streptolysin-O, aerolysin, maltoporin, P2X7, melittin),
mechanical stress (e.g. sonication, vortex mixing), and the like” (Doranz
¶ 555).
9. Hans teaches a “vortex structure represents an area of lower
pressure and density than in the surrounding fluid” (Hans 122, col. 2).
Principles of Law
A prima facie case for obviousness “requires a suggestion of all
limitations in a claim,” CFMT, Inc. v. Yieldup Int’l Corp., 349 F.3d 1333,
1342 (Fed. Cir. 2003), and “a reason that would have prompted a person of
ordinary skill in the relevant field to combine the elements in the way the
claimed new invention does.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398,
418 (2007).
Analysis
We do not agree with Appellant that a teaching, suggestion, and
motivation test is required to render method claims obvious, instead KSR
requires a reason to combine teachings in the prior art. KSR, 550 U.S. at
418. However, we agree with Appellant that the Examiner has not
identified a reason to modify the method of Sharei, in which cell constriction
is used to introduce material into cell cytosols, with flow diverters having a
gap “greater than the diameter of the cell” as required by claim 1.
The Examiner acknowledges a “difference between Sharei and the
instant invention is that Sharei uses squeezing and not a vortex street to
induce the transient holes” (Ans. 9). The Examiner responds that “the prior
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art indicates functional equivalency between squeezing and vortices with
respect to creating transient holes in cell lipid membranes” (id.).
We are not persuaded. Sharei requires a constriction and specifically
finds that longer constriction lengths and narrower constrictions resulted in
greater delivery efficiency into cells (FF 4). This is the opposite of the
requirement of the claim for gaps wider than the cell diameter. Clarke and
Hans provide no information regarding delivery of material into cells (FF 5–
7, 9).
And we find the Examiner’s reliance on Doranz for vortices
particularly unpersuasive, because Doranz is clearly referring to a vortex
mixer, a simple common laboratory device used to mix microcentrifuge
tubes or other small vials (FF 6). Doranz is not referring to microfluidic
devices such as those of Sharei. Doranz does not reasonably suggest that
vortices in microfluidic devices are equivalent to constriction in microfluidic
devices. Doranz therefore lacks evidence that vortices in microfluidic
devices would reasonably be expected to result in the cell poration obtained
in Sharei’s device.
We therefore agree with Appellant that this rejection relies on
hindsight. “We must still be careful not to allow hindsight reconstruction of
references to reach the claimed invention without any explanation as to how
or why the references would be combined to produce the claimed
invention.” Innogenetics, N.V. v. Abbott Labs., 512 F.3d 1363, 1374 n.3
(Fed. Cir. 2008).
Because we find that the Examiner did not establish a prima facie case
of obviousness, we need not address the arguments regarding secondary
considerations.
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Conclusion of Law
(i) A preponderance of the evidence of record does not support the
Examiner’s conclusion that the prior suggests the method of claim 1.
(ii) We do not address the secondary consideration evidence.

B.–C. 35 U.S.C. § 103(a)
Having reversed the obviousness rejection of claim 1 for the reasons
given above, we also find that the Examiner does not point to teachings in
the additionally cited prior art that provide a reason to modify the device of
Sharei to replace a device that constricts cells with a device that has wider
gaps and creates vortices. We therefore reverse these rejections for the same
reasons as given above.
DECISION SUMMARY
In summary:
Claim(s)
Rejected
35
U.S.C. §
Reference(s)/Basis Affirmed Reversed
1, 2, 4–7,
17, 22–33,
36–43
103 Sharei, Clarke, Doranz,
Hans
1, 2, 4–7,
17, 22–33,
36–43
1, 2, 4–7,
17, 21–33,
36–43
103 Sharei, Clarke, Doranz,
Hans, Diefenbach
1, 2, 4–7,
17, 21–33,
36–43
1, 2, 4–7,
17, 22–43
103 Sharei, Clarke, Doranz,
Hans, Hejna
1, 2, 4–7,
17, 22–43
Overall
Outcome
1, 2, 4–7,
17, 21–43

REVERSED