DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 10/08/2025 has been entered.
Status of Claims
Claims 1 and 10-12 are pending and examined on the merits.
Claims 2-9 are cancelled.
Status of Prior Rejections/Response to Arguments
RE: Rejection of claim(s) 1 and 10 under 35 U.S.C. 103 as being unpatentable over Goudar (Sensors and Actuators B: Chemical, 2020), in view of Skardal (WO 2019/152767).
RE: Rejection of claim(s) 1 and 4-10 are under 35 U.S.C. 103 as being unpatentable over Goudar (Sensors and Actuators B: Chemical, 2020), in view of Skardal (WO 2019/152767) and Kovac (Advanced Healthcare Materials, 2012), as evidenced by Chemical Book (chemicalbook.com).
RE: Rejection of claims 1 and 10-12 under 35 U.S.C. 103 as being unpatentable over Goudar (Sensors and Actuators B: Chemical, 2020), in view of Skardal (WO/2019/152767) and Wei (Sensors and Actuators B: Chemical, 2019).
The amendment to independent claim 1 to include the limitations of dependent claims 2-3 is effective to differentiate the claim from Gourdar, in view of Skardal. Claims 10-12 depend from claim 1. The rejections are withdrawn. The cancellation of claims 4-9 renders the rejection thereof moot.
RE: Rejection of claim(s) 1-3 under 35 U.S.C. 103 as being unpatentable over Goudar (Sensors and Actuators B: Chemical, 2020), in view of Skardal (WO 2019/152767) and Kamei (WO/2015/129673), as evidenced by Klouda (Eur J Pharm Biopharm, 2008).
Applicant has traversed the rejection on the grounds that Kamei does not clearly disclose how to adjust the gel concentration to achieve the purpose and unexpected effects of “precisely identifying and screening target cells and then accurately aspirating the target cells individually” of the present application, and therefore, that a person of ordinary skill in the art would not have motivated to combine the teaching of Kamei with the other references cited. Applicant also argues that although though Koluda states that gelatin is a thermoresponsive hydrogel that solidifies at temperatures below 25°C, it does not explicitly mention the specific gelatin concentration range of the present application.
Upon reconsideration, the rejection of record is being withdrawn in favor of a new ground of rejection, as set forth below in this Office Action. The new reference, Bishard (WO 2021/091388 A1), does teach a temperature-sensitive hydrogel solution comprising 3% to 5% by gelatin.
Claim Objections
Claims 1 and 11 are objected to because of the following informalities:
Claim 1 recites the phrase “adding a hydrogel solution and mixing the same with the cell mixture to form a mixture solution” (lines 7-8; emphasis added). “The same” is interpreted as “a hydrogel solution” of line 7. For the sake of clarity, it is recommended that the claim is amended to recite “adding a hydrogel solution and mixing the hydrogel solution with the cell mixture to form a mixture solution.”
Claim 11 is drawn to “A cell sorting method of claim 1” (line 1). For the sake of clarity, it is recommended that the claim be amended to recite “The cell sorting method of claim 1.”
Appropriate correction is required.
Claim Interpretation
Claim 1 recites the phrase “automatic aspirator” (line 15), which is not defined in the specification. Fig. 3C of the Drawings filed 04/25/2022 depict an “automatic aspirator PP of the computer-programmable electric single-cell extraction and injection system to obtain the target cells C1 by quantitative aspiration at a fixed flow rate” (p 13, para 42 of specification; the acronym “PP” is not defined). Based on this description, the phrase “automatic aspirator” is interpreted to mean a pipetting device having quantitative aspiration at a fixed flow rate.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 1 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
The term “substantially” in line 10 of claim 1 is a relative term which renders the claim indefinite. The term “substantially” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. In the absence of a definition in the specification, it is unclear how, or if, “a substantially monolayer manner” (line 10) differs from “a monolayer manner.”
Furthermore, the phrase “wherein the step of curing the mixture solution comprises performing a cooling process to cure the mixture solution, fixing positions of the target cells and the non-target cells” (lines 18-19) renders the claim indefinite. Although “performing a cooling process” and “fixing positions” are both recited as active steps in the method, an ordinary artisan cannot envisage how to fix (understood in this context as adjust) positions of cells after the mixture solution has been cured. Alternatively, the phrase may be understood to mean “wherein the step of curing the mixture solution comprises performing a cooling process to cure the mixture solution, thereby fixing positions of the target cells and the non-target cells.” The latter interpretation is used for the purposes of examination.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1 and 10 are rejected under 35 U.S.C. 103 as being unpatentable over Goudar (Sensors and Actuators B: Chemical, 2020), in view of Skardal (WO 2019/152767) and Bishard (WO 2021/091388 A1).
Goudar teaches a method for selecting circulating tumor cells (CTCs) from whole blood on digitized self-assembled cell array (Digi-SACA) chips (Abstract; Title). The method comprises obtaining peripheral blood samples from human patients (claim 1), centrifuging the whole-blood sample to obtain a mixture comprising CTCs (reads on target cells) and white blood cells (reads on non-target cells) (claims 1 and 10), staining the samples with fluorescent markers (claim 1), loading the cells onto the SACA chip (reads on array chip) to form a dense monolayer (claim 1), using an automatic imaging system to scan and count CTCs based on fluorescent signals (claim 1), and picking the CTCs using a cell-picking needle connected to a micropump (claim 1) (p 3, Section 2.3; Fig 2). The cell-picking device comprises a 20-40 µm-orifice glass pipette connected via tube to a micropump with a flow rate of 40 µl/min (p 5, Section 2.8; Fig 4; reads on automatic aspirator).
Goudar does not teach a hydrogel solution to be mixed with the cells.
Skardal teaches mixing patient-derived tumor cells with hydrogel and introducing the mixture into a microfluidic chamber (p 4, para 4), then illuminating the mixture with UV light through a photomask to crosslink the solution (reads on curing the mixture solution) (p 4, para 4). Skardal teaches that the exposed precursor is crosslinked into the hydrogel, detaining cells within the region, and non-crosslinked gel is flushed from the chamber (p 4, para 4). Skardal teaches that curing the cell/hydrogel mixture allows the researcher to define the shape and location of the mixture on the substrate (p 37, para 4 – p 38, para 1).
It would have been prima facie obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the method of Goudar by adding a hydrogel solution to the cell mixture, as taught by Skardal. One of ordinary skill in the art would have been motivated to make this modification because Skardal teaches that curing the cell/hydrogel mixture allows the researcher to define the shape and location of the mixture on the substrate (p 37, para 4 – p 38, para 1). One of ordinary skill in the art would have had a reasonable expectation of making this modification because Skardal teaches that the cell/hydrogel mixture can be spread onto and cured on a microfluidic chamber, and that fluorescent imaging can be performed on cells cultured in the cell/hydrogel mixture (p 47, para 1-3).
Goudar, in view of Skardal, does not teach a temperature-sensitive hydrogel solution comprising 3% to 5% by weight of gelatin, or performing a cooling process to cure the mixture solution.
Bishard teaches a microfluidic cell culture system comprising a cell culture chamber with a reversible solidifying medium (p 7, para 3). The reversible solidifying medium, which comprises a solidifying agent and an aqueous medium, is added in liquid form to the cell culture chamber, after which the reversible solidifying medium is allowed to solidify (p 7, para 4). The reversible solidifying medium is removed from the system by melting and subsequently aspirating (p 8, para 2). Bishard teaches that the preferred solidifying agent in the reversible solidifying medium is gelatin at about 3% to about 6% by mass compared to the total mass of the reversibly solidifying medium (p 7, para 5 – p 8, para 1). The reversible solidifying medium comprising gelatin reads on hydrogel solution. Bishard teaches specific examples, wherein 5% gelatin medium (Fig 3; description on p 14-16) or 4% gelatin medium (Fig 4; description on p 16) is added to an OrganoPlate microfluidic culture plate (Fig 3 and Fig 4, respectively).
It would have been prima facie obvious for a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the method of Goudar, in view of Skardal, by substituting the photosensitive hydrogel solution of Skardal with a temperature-sensitive hydrogel solution comprising 3% to 5% by weight of gelatin, as taught in Bishard. One of ordinary skill in the art would have been motivated to make this modification Bishard teaches that temperature-sensitive hydrogel can be melted and removed from the system by aspiration (p 8, para 2), thereby allowing the recovery of the samples. One of ordinary skill in the art would have had a reasonable expectation of making this modification because Bishard teaches that a gelatin hydrogel is compatible with a microfluidic cell culture system.
Claims 11-12 are rejected under 35 U.S.C. 103 as being unpatentable over Goudar (Sensors and Actuators B: Chemical, 2020), in view of Skardal (WO/2019/152767) and Bishard (WO 2021/091388 A1), and further in view of Wei (Sensors and Actuators B: Chemical, 2019).
The teachings of Goudar, Skardal, and Bishard are set forth above.
Goudar, in view of Skardal and Bishard, renders obvious independent claim 1.
Following the discussion of claim 1, Goudar teaches staining the centrifuged cells with a FITC-labeled anti-cytokeratain antibody, which is positive to the target CTCs, and a PeCy7-labeled anti-CD45 antibody, which is negative to the target CTCs (Fig 5).
Goudar, in view of Skardal and Bishard, does not teach a cell sorting method according to claim 1, wherein the target cells are fetal nucleated red blood cells, or the use of anti-CD147 or anti-CD71 antibodies.
Wei teaches a method for isolating fetal nucleated red blood cells (claim 11) from maternal peripheral blood using a microfluidics device modified with anti-CD147 as a specific capture antibody for fetal nucleated red blood cells (Abstract; p 136, col 1, para 2). Wei teaches performing immunofluorescence using DAPI (p 132, col 2, para 2; p 136, col 2, para 1; reads on 4',6-diamidino-2-phenylindole of claim 12) and FITC-labeled anti-CD71 to distinguish fetal nucleated red blood cells from white blood cells (p 133, col 2, para 3; p 136, col 2, para 1). Wei teaches that the target fetal nucleated red blood cells are positive for both DAPI and CD71, and the non-target white blood cells are positive for DAPI but negative for CD71 (p 136, col 2, para 1).
It would have been prima facie obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the method of Goudar, in view of Skardal and Bishard, by using fetal nucleated red blood cells as the target cells, an anti-CD71 antibody with a fluorescent substance, and DAPI, as taught in Wei. One of ordinary skill in the art would have been motivated to make this modification because Wei teaches that fetal nucleated red blood cells in maternal peripheral blood has the potential for use in non-invasive prenatal diagnostics (Abstract). One of ordinary skill in the art would have had a reasonable expectation of successfully making this modification because Goudar teaches that fluorescent-labeled antibodies can be used to sort target and non-target cells from whole blood samples on the Digi-SACA system.
Wei does not teach the use of an anti-CD147 antibody with a fluorescent substance (claim 11). Wei teaches that in addition to DAPI and FITC-anti-CD71, PE-anti-ε-globin was used in the immunofluorescent experiment (Fig 5A). Wei teaches that the target fetal nucleated red blood cells are positive for both ε-globin and CD147 (p 136, Section 3.4).
Given the teachings of Wei, there was a reasonable expectation that ε-globin and CD147 would work equivalently as an antibody to identify fetal nucleated blood cells. Therefore, it would have been prima facie obvious to a person of ordinary skill before the effective filing date of the claimed invention to have substituted the ε-globin primary antibody with a CD147 antibody with predictable results. Substitution of one element for another known in the field, wherein the result of the substitution would have been predictable, is considered to be obvious. See KSR International Co. v Teleflex Inc 82 USPQ2d 1385 (US 2007) at page 1395.
Conclusion
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/RISA TAKENAKA/Examiner, Art Unit 1632
/TITILAYO MOLOYE/Primary Examiner, Art Unit 1632