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 allowance or after an Office action under Ex Parte Quayle, 25 USPQ 74, 453 O.G. 213 (Comm'r Pat. 1935). 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, prosecution in this application has been reopened pursuant to 37 CFR 1.114. Applicant's submission filed on 06/02/2026 has been entered.
Priority
Applicant’s claim for the benefit of a prior-filed application under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, 365(c), or 386(c) is acknowledged. Acknowledgment is made of applicant’s claim for foreign priority under 35 U.S.C. 119 (a)-(d). The certified copy has been filed in parent Application No. 17/182,749, filed on 02/23/2021.
This application claims benefit of the foreign application EPO 19179087.2 filed 06/07/2019. Based on the filing receipt, the effective filing date of this application is June 7, 2019 which is the filing date of Application EPO 19179087.2 from which the benefit of priority is claimed.
Status of Claims
Claims 1-30 have been cancelled by the Applicant.
Claims 31-51 are pending and examined herein.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 31-32, 35, 37-47, and 49-51 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Vladimirovich (“NON-INVASIVE DIAGNOSTICS OF ANEUPLOIDY OF A FETUS WITH CIRCULATING TROPHOBLAST CELLS IN MATERNAL BLOOD”, published 2016, cited in IDS filed 04/08/2026) as evidenced by Zhang (“Evolution of TROP2: Biological insights and clinical applications”, published 2025) and the technical manual for ReliaPrep™ Blood gDNA Miniprep System by Promega (revised 2021-09).
With respect to claim 31, Vladimirovich teaches a method of isolating a fetal trophoblast cell from maternal blood comprising the steps of:
A. providing a blood sample from a woman carrying a fetus;
B. enriching said blood sample for fetal trophoblasts,
C. contacting the enriched cells with at least one labelling agent selected from each of the groups to form labelled cells:
i. a fluorescent labelling agent directed against the nucleus,
ii. a fluorescent labelling agent directed against a maternal cell marker, and
iii. a fluorescent labelling agent directed against a fetal trophoblast marker; and D. single cell sorting the labelled cells on a fluorescence activated cell sorter (FACS), wherein fetal trophoblast cells are single cell sorted into single cell compartments based on:
i. positive selection of said labelling agent directed against a fetal trophoblast marker,
ii. positive selection of said labelling agent directed against the nucleus, and
iii. negative selection of said labelling agent directed against a maternal cell marker (see, e.g., a method of isolating fetal trophoblast cells from maternal blood – p. 1, under abstract; step A. – p. 4, para. 1; step B. – p. 6, para. 1; step C., sub-step i. – p. 5, para. 1: “For reliable discrimination of nucleated cells, they were stained with Hoechst 33342”; step C., sub-step ii. – p. 6, para. 2: “Within the gate of live, virulent cells negative for the pan-leukocyte marker (CD45) […] was isolated”; step C., sub-step iii. – p. 6, para. 2: “Within the gate of live, virulent cells […] a double positive gate, HLA-G Trop-2, was isolated”; step D. - p. 5, para. 1: “For reliable discrimination of nucleated cells, they were stained with Hoechst 33342”, and p. 6, para. 2: “Within the gate of live, virulent cells negative for the pan-leukocyte marker (CD45), a double positive gate, HLA-G Trop-2, was isolated”).
With respect to claims 32 and 35, Vladimirovich teaches the labelling agent directed against a fetal trophoblast marker is a labelling agent directed against an epithelial marker (see, e.g., p. 6, para. 2: “Within the gate of live, virulent cells negative for the pan-leukocyte marker (CD45), a double positive gate, HLA-G Trop-2, was isolated”, emphasis added). Trop-2 is an epithelial marker as evidenced by Zhang (see, e.g., p. 3, col. 1, under “2.2.2. TROP2 in normal tissue and development”: “The expression of the TROP2 protein is relatively low in healthy human tissues, but it exists in various epithelial cells”).
With respect to claim 37, Vladimirovich teaches the labeling agents are antibodies (see, e.g., p. 5, para. 1: “Three-color staining was performed with monoclonal antibodies (Biolegend Inc., USA) against HLA-G labeled with allophycocyanin with CD41a (APC), Trop-2 labeled with phycoerythrin (PE), and CD45 labeled with fluorescein isothiocyanate (FITC)”.
With respect to claim 38, Vladimirovich teaches wherein at least one of said labelling agents are indirectly and/or directly labelled by at least one fluorophore (see, e.g., p. 5, para. 1: “Three-color staining was performed with monoclonal antibodies (Biolegend Inc., USA) against HLA-G labeled with allophycocyanin with CD41a (APC), Trop-2 labeled with phycoerythrin (PE), and CD45 labeled with fluorescein isothiocyanate (FITC)”.
With respect to claim 39, Vladimirovich teaches wherein said fluorophore is FITC (see, e.g., p. 5, para. 1: “Three-color staining was performed with monoclonal antibodies (Biolegend Inc., USA) against HLA-G labeled with allophycocyanin with CD41a (APC), Trop-2 labeled with phycoerythrin (PE), and CD45 labeled with fluorescein isothiocyanate (FITC)”.
With respect to claim 40, Vladimirovich teaches the labeling agent directed against the nucleus is a Hoechst dye (see, e.g., p. 5, para. 1: “For reliable discrimination of nucleated cells, they were stained with Hoechst 33342).
With respect to claim 41, Vladimirovich teaches the labeling agent directed against a maternal cell marker is a labeling agent directed against a leucocyte marker, specifically CD45 (see, e.g., p. 6, para. 2: “Within the gate of live, virulent cells negative for the pan-leukocyte marker (CD45), a double positive gate, HLA-G Trop-2, was isolated”).
With respect to claim 42, Vladimirovich teaches wherein said fetal trophoblasts are identified by obtaining a genotype from said fetal trophoblasts by STR analysis (see, e.g., p. 5, para. 1: “The amplified DNA was then used to perform quantitative fluorescence polymerase
chain reaction (QF-PCR) using the Aneufast Multiplex QF-PCR Kit (Genomed, United Kingdom) containing markers for short tandem repeats (STR) of microsatellite DNA of chromosomes most susceptible to numerical aberrations (13, 18, 21, X, and Y)”, emphasis added).
With respect to claim 43, Vladimirovich teaches the method further comprises detecting one or more markers associated with a genetic abnormality in the genome of the fetal trophoblast cell (see, e.g., under title: “NON-INVASIVE DIAGNOSTICS OF ANEUPLOIOY OF A FETUS WITH CIRCULATING TROPHOBLAST CELLS IN MATERNAL BLOOD”).
With respect to claim 44, Vladimirovich teaches wherein the one or more markers are detected by Short Tandem Repeat analysis (STR analysis) (see, e.g., p. 5, para. 1: “The amplified DNA was then used to perform quantitative fluorescence polymerase chain reaction (QF-PCR) using the Aneufast Multiplex QF-PCR Kit (Genomed, United Kingdom) containing markers for short tandem repeats (STR) of microsatellite DNA of chromosomes most susceptible to numerical aberrations (13, 18, 21, X, and Y)”, emphasis added).
With respect to claim 45, Vladimirovich teaches wherein the genetic abnormality is aneuploidy (see, e.g., under title: “NON-INVASIVE DIAGNOSTICS OF ANEUPLOIOY OF A FETUS WITH CIRCULATING TROPHOBLAST CELLS IN MATERNAL BLOOD”).
With respect to claim 46, Vladimirovich teaches wherein the blood sample is 10 mL (see, e.g., p. 4, para. 2: “Heparinized peripheral venous blood from pregnant women (10 ml) was processed”).
With respect to claim 47, Vladimirovich teaches where the blood sample comprises a cellular fraction separated from plasma (see, e.g., p. 4, para. 2: “After centrifugation at 800xg for 30 min at room temperature, mononuclear cells were transferred to a separate 15 ml tube and washed twice in buffer (0.5% BSA in PBS with 2 MM EDTA)”).
With respect to claim 49, Vladimirovich teaches the cellular fraction comprises both maternal white blood cells and fetal trophoblast cells (see, e.g., maternal white blood cells - para. spanning p. 4-5: “After centrifugation at 800xg for 30 min at room temperature, mononuclear cells were transferred to a separate 15 ml tube and washed twice in buffer (0.5% BSA in PBS with 2 MM EDTA). The resulting mononuclear cell sample (~2x107 cells in 800 μI) was subjected to negative immunomagnetic separation using the BD Human Lineage Cell Depletion Set (BD Biosciences, USA), according to the manufacturer's instructions. The initial mononuclear cell sample was depleted of markers of mature linearly differentiated cells: CD3 (T cells), CD19 (B cells), CD16 and CD56 (NK cells), (platelets) and CD235a (erythrocytes) antibodies”; fetal trophoblast cells – under title: “NON-INVASIVE DIAGNOSTICS OF ANEUPLOIOY OF A FETUS WITH CIRCULATING TROPHOBLAST CELLS IN MATERNAL BLOOD”).
With respect to claim 50, Vladimirovich teaches the method further comprising a step of selectively lysing red blood cells of said cellular fraction using a detergent subsequent to separation of said cellular fraction from said plasma fraction, wherein said lysing also permeabilizes the remaining cells in said cellular fraction (see, e.g., p. 5, para. 1: “Extraction of maternal and paternal DNA was performed by the sorption method using the ReliaPrep™ Blood gDNA Miniprep System reagent kit (Promega, USA) from a 200 μI blood sample”). Promega gives evidence of the lysing (see, e.g., p. 2, under “2. Product Components and Storage Conditions”: “Cell Lysis Buffer (CLD)”).
With respect to claim 51, Vladimirovich teaches wherein the enrichment is performed with magnetic activated cell sorting (MACS) (see, e.g., p. 4, para. 2: “The resulting mononuclear cell sample (~2x107 cells in 800 μI) was subjected to negative immunomagnetic separation using the BD Human Lineage Cell Depletion Set (BD Biosciences, USA), according to the manufacturer's instructions”).
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.
Claims 33-34, 36, and 48 are rejected under 35 U.S.C. 103 as being unpatentable over Vladimirovich (cited above), as applied to claims 31-32, 35, 37-47, and 49-51, and further in view of Eckelt (EP 2638176 B1, published 2017-08-23, cited in PTO-892 dated 06/03/2025).
Vladimirovich teaches as set forth above, but fails to teach wherein the labelling agent directed against a fetal trophoblast marker is a labelling agent directed against an endothelial marker, specifically CD105, as in claims 33-34. Vladimirovich also fails to teach the epithelial marker is a cytokeratin, as in claim 36. Vladimirovich also fails to teach the method further comprising a step of fixating the cells in said blood sample subsequent to being separated from said plasma fraction, as in claim 48
However, Eckelt teaches the labeling agents directed against CD105 and cytokeratins, as in claims 33-34 and 35 (see, e.g., CD105 – para. [0032]: “Thus, in one embodiment the sample is contacted with a hybridization probe or ligand directed to an endothelial cell marker […] Most preferred is CD105”; cytokeratins - para. [0149]). Eckelt also teaches the method further comprising a step of fixating the cells in said blood sample subsequent to being separated from said plasma fraction, as in claim 48 (see, e.g., para. [0019]: “In one embodiment of the invention the discovery that fixation of the cells of a maternal blood sample greatly increases stability of fetal cells in a maternal blood sample, while allowing enrichment and identification of fetal cells e.g. as further described herein above. In one embodiment the fixation procedure can be performed on a non-enriched blood sample immediately after sampling”).
Vladimirovich and Eckelt are analogous to the field of the claimed invention because they are both in the field of fetal cell isolation. One of ordinary skill in the art before the effective filing date of the application would have found it obvious to incorporate the markers of Eckelt into the method of Vladimirovich. An artisan would have been motivated to do so because Eckelt discloses that CD105 is “Most preferred” (see, para. [0032]). Eckelt also discloses, “These results demonstrate, that CD105 based magnetic cell sorting (MACS) of maternal blood samples reveal a novel fetal cell type in maternal blood expressing cytokeratins and/or vimentin, thus discriminating this cell type from fetal trophoblasts” (see, para. [0154]). One of ordinary skill in the art before the effective filing date of the application would have found it obvious to incorporate the fixation of Eckelt into the method of Vladimirovich. An artisan would have been motivated to do so because Eckelt discloses, “fixation of the cells of a maternal blood sample greatly increases stability of fetal cells in a maternal blood sample” (see, para. [0019]). An artisan would have had a reasonable expectation of success based on the given disclosures.
Double Patenting
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13.
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
Claims 31-51 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-30 of U.S. Patent No. 9,429,520 and further in view of Vladimirovich (cited above) and Eckelt (cited above).
Although the claims at issue are not identical, they are not patentably distinct from each other because the ‘520 claims are directed to a method of detecting cells having a combined endothelial-epithelial phenotype, said method comprising the steps of: a) providing a blood sample from a pregnant woman, or a fraction thereof; b) contacting the sample or a fraction thereof with a hybridization probe comprising at least 10 contiguous nucleotides complementary to a gene encoding an endothelial cell marker or a ligand directed to an endothelial cell marker, wherein said endothelial cell marker is selected from the group consisting of CD105, CD146, CD141, vimentin, VCAM, ICAM, VEGFR-1, VEGFR-2, VEGFR-3, ITGA5, ITGB5, CDH11, and CDH3; c) selecting the cells expressing said endothelial cell marker, thereby obtaining a population of cells enriched in cells expressing said endothelial cell marker; d) contacting the enriched population of cells with a hybridization probe comprising at least 10 contiguous nucleotides complementary to a gene encoding an epithelial cell marker or a ligand directed to an epithelial cell marker, wherein said epithelial cell marker is selected from the group consisting of CK1, CK2, CK3, CK4, CK5, CK6, CK7, CK8, CK9, CK10, CK13, CK14, CK15, CK16, CK17, CK18, and CK19; and e) detecting cells expressing said epithelial cell marker in the cells obtained in step d as having a combined endothelial-epithelial phenotype. The claims of the patent are thus directed to prenatal diagnostic methods as claimed in the instant application via cell sorting with the same markers encompassed by the instant claims in order to arrive at sorted fetal cells. The patent claims differ in scope from the instant claims, as the patent claims utilize hybridization methods to separate and sort the cells in the blood sample, while the instant claims use both MACS and FACS methods.
However, all of these methods are considered obvious variants of each other as disclosed by Vladimirovich and Eckelt. Eckelt repeatedly teaches throughout the document that one can use either hybridization methods or MACS and FACS methods to separate and sort the cells from the maternal blood sample (see e.g. [0011] and [0092]-[0094] for example). Vladimirovich and Eckelt’s additional teachings are set forth above.
It would have been prima facie obvious to the person of ordinary skill in the art to arrive at the claimed invention from the disclosures of the ‘520 patent claims, Vladimirovich, and Eckelt. The person of ordinary skill in the art would have been motivated to make and use the claimed invention because Eckelt teaches methods of fetal cell isolation, wherein fetal trophoblasts are positively selected through a fluorescent marker directed to a fetal trophoblast marker (e.g. CD105), are negatively selected through a fluorescent marker to a maternal cell marker (e.g. CD45). The artisan would have been additionally motivated because Eckelt teaches that one can preferably use MACS and FACS for multiple rounds of enrichment and FACS for the final step of detection and because Eckelt teaches that the nucleus can be visualized and identified with a fluorescent marker in the final identification step (e.g. DAPI)(citations above). Vladimirovich provides the motivation to use nuclear DAPI staining for single cell sorting FACS to isolate the fetal trophoblasts as an alternative to Eckelt’s nuclear staining and visualization methods. The person of ordinary skill in the art would have been motivated to use Vladimirovich’s whole genome sequencing of fetal trophoblast cells because Vladimirovich teaches that the method reflects the genome of the fetus and not that of the mother and has the ability to analyze multiple single cells which allows for verification of the fetal origin of the isolated cells (see, e.g., p. 10, para. 2). The person of ordinary skill in the art would have had a reasonable expectation of success based on the cumulative disclosures of these prior art references.
Conclusion
No claims are allowed.
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/MICHAEL CAMERON SVEIVEN/ Examiner, Art Unit 1678
/GREGORY S EMCH/ Supervisory Patent Examiner, Art Unit 1678
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