Nd 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 .
Applicant's amendments to the claims and arguments filed on 02-04-2026 have been received and entered. Claims 8, 17, 23 have been amended. Claims 1-7, 12-16, 18-19, 21-22, 24-29, 31, 33-36, 38-40, 42-43, 45-62 have been canceled. Claims 8-11, 17, 20, 23, 30, 32, 37, 41, 44, 63-70 are pending in the instant application.
Election/Restrictions
Applicant's election with traverse of Group I, claims 8-11, 17, 20, and 23, in the reply filed on 08-31-2025 is acknowledged. The traversal is on the ground(s) that claims 8, 30, and 41 are amended to each recite that the three-dimensional cell culture comprises “oxygen in an amount of less than about 10%, and carbon dioxide in an amount of less than about 10%.”, and as a result, Groups I, II, and III each share a technical feature of obtaining a population of CTCs.
This is not found persuasive because even though the base claims 8, 30, and 41 are amended to include “oxygen in an amount of less than about 10%, and carbon dioxide in an amount of less than about 10%”, this is not a technical feature of obtaining a population of circulating tumor cells (CTCs) in view of Yu et al (Science. 2014 Jul 11;345(6193):216-20. doi: 10.1126/science.1253533.) as described in the preceding OA mailed on 11-04-2025 and the new 35 USC § 103 rejection necessitated by amendments below.
The requirement is still deemed proper and is therefore made FINAL as described in the preceding OA mailed on 11-04-2025.
Claim 30, 32, 37, 41, 44, 63-70 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected subject matter, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on.
Claims 8-11, 17, 20, and 23 are under consideration.
Priority
This application is a 371 of PCT/US2021/029244 filed on 04/26/2021 that claims priority from US provisional application 63/015,665 filed on 04/26/2020.
Maintained in modified form - Claim Rejections - 35 USC § 112-necessitated by amendments
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.
Claims 8-11, 17, 20, and 23 are 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.
Claim 8 recites the phrases “less than about” which render the claim indefinite because “About” encompasses values above and below of a reference point whereas “less than” encompassesonly values below the reference point. Therefore, the combination of both terms (less than about) isunclear because one term is including values above the reference point whereas the other term isexcluding values above the reference point.
Claims 9-11, 17, 20, 23 are included in the rejection because they directly or indirectly depend from base claim. Appropriate correction is required.
Response to Arguments
Applicant's arguments filed on 02-04-2026 have been fully considered but they are not persuasive.
Applicants argue that the combination of "less than" and "about" in regard to a recited value does not render the claim indefinite. As acknowledged in MPEP 2173.05(b)(III), "about" indicates a range encompassed around a recited value. Therefore, "less than about" means that the scope covers less than this range that is encompassed around the recited value; the scope does not just cover less than the recited value. As further support for this argument, the MPEP, in that same section, cites WL. Gore & Associates, Inc. v. Garlock, Inc., 721 F.2d 1540 (Fed. Cir. 1983), in which the court held that a limitation defining the stretch rate of a plastic as "exceeding about 10% per second" is definite, even though the term "exceeding" and "about" were used together (Remark, page 7-8).
Response to Arguments:
Applicant cited MPEP 2173.05(b)(III) to argue the term “less than about” is definite because the scope covers less than this range that is encompassed around the recited value; however, Applicant ignore the fact that MPEP 2173.05(b)(III) further states that “in another case, the court held that claims reciting "at least about" were invalid for indefiniteness where there was close prior art and there was nothing in the specification, prosecution history, or the prior art to provide any indication as to what range of specific activity is covered by the term "about." Amgen, Inc. v. Chugai Pharmaceutical Co., 927 F.2d 1200, 18 USPQ2d 1016 (Fed. Cir. 1991).”. In the instant case, the instant disclosure does not provide any indication as to what range of amount of oxygen is covered by the term "about". A person of ordinary skill in the art would not know what “range” can be included or excluded for the terms “oxygen in an amount of less than about 2%” because the term “about” encompasses values above and below of a reference point whereas “less than” encompasses only values below the reference point. Therefore, the combination of both terms (less than about) is unclear because one term is including values above the reference point whereas the other term is excluding values above the reference point.
Withdrawn - Claim Rejections - 35 USC § 103
Claims 8, 9, 10 and 23 were rejected under 35 U.S.C. 103 as being unpatentable over Hua et al (CN 109207428 A, Date Published: 2019-01-15) in view of Yu et al (Science. 2014 Jul 11;345(6193):216-20; doi: 10.1126/science.1253533; 11 JULY 2014). In view of Applicants' amendment of base claim 8, introducing the limitation “oxygen in an amount of less than about 2%”, the previous rejections of claims are hereby withdrawn. Applicants' arguments with respect to the withdrawn rejections are thereby rendered moot. The claims are however subject to new rejections over the prior art of record, as set forth below.
Claim 11 was rejected under 35 U.S.C. 103 as being unpatentable over Hua et al (CN 109207428 A, Date Published: 2019-01-15) in view of Yu et al (Science. 2014 Jul 11;345(6193):216-20; doi: 10.1126/science.1253533; 11 JULY 2014) as applied to claims 8, 9, 10 and 23 above, and further in view of Hughes et al (J. Vis. Exp. (64), e4248, doi:10.3791/4248 (2012)). The rejection is withdrawn for the reasons discussed above.
Claims 17 and 20 were rejected under 35 U.S.C. 103 as being unpatentable over Hua et al (CN 109207428 A, Date Published: 2019-01-15) in view of Yu et al (Science. 2014 Jul 11;345(6193):216-20; doi: 10.1126/science.1253533; 11 JULY 2014) as applied to claims 8, 9, 10 and 23 above, and further in view of Zhang et al (Pub. No .: US 2021/0189351 A1, Provisional application No. 62/720,010 , filed on Aug. 20, 2018). The rejection is withdrawn for the reasons discussed above.
New-Claim Rejections - 35 USC § 103- necessitated by amendments
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 8, 9, 10 and 23 are rejected under 35 U.S.C. 103 as being unpatentable over Hua et al (CN 109207428 A, Date Published: 2019-01-15) in view of Lim et al (Pub. No.: US 2018/0066223 A1, Pub. Date: Mar. 8, 2018).
Claim interpretation:
The specification of the claimed invention teaches that “CTCs do not include cells originating from blood born cancers, such as leukemia, lymphoma, or myeloma” ([0048], page 10). Thus, blood born cancers are interpreted as leukemia, lymphoma, or myeloma.
Regarding to claim 8, the preamble, Hua et al teach “Separating and culturing method of circulating tumor cells” (title).
Regarding to claim 8, step a and b:
Hua et al teach “the peripheral blood taken from an organism afflicted with cancer, the cancer comprises gastric cancer, intestinal cancer, lung cancer, gallbladder cancer, or pancreatic cancer” (Page 3, 8th para.)
Hua et al teach “the method comprises: removing the anticoagulant peripheral blood CD45 positive cells by Human CD45 Depletion Calyculin kit, so as to obtain CD45-negative cell solution; using density gradient centrifugation processing to the CD45 negative cell solution, collecting the centrifuged upper layer and middle layer of the cell solution, and the cells in the cell solution to culture. Because CTCs usually is CD45 -, so the kit removed in peripheral blood CD45 + cells, to avoid extracting interference caused by non-CTCs …... the inventor kit to obtain CD45 negative cell solution to density gradient centrifugation, using peripheral blood in different cell populations with different specific gravity characteristic, separating the CTCs after centrifuging, ……the separation and culture method of circulating tumor cells according to the embodiment of the invention can effectively enrich circulating tumor cells, high yield, good purity, convenient in operation and suitable for large-scale application” (see bridging last paragraph page 2-3). It is noted that as described above, Hua et al teach the removal of CD45 + cells which are leukocytes, “separating the CTCs” and only keep CD45 – CTC cells with “good purity” by “separating the CTCs after centrifuging” (see bridging last paragraph page 2-3). Thus, Hua et al teach separation of CTCs with “good purity” from any other cells (such as erythrocytes or leukocytes or any other cells) so that it satisfies the requirement of “separate the CTCs from at least erythrocytes in the whole blood sample”. Hua implicitly teaches separation/isolation of CD 45- CTC cells from erythrocytes since they were only interested in CTC cells.
Regarding to claim 8, step c: Hua et al teach “…… the invention is not strictly limited to the cultivation method of the CTCs, can be flexibly selected according to actual need, the best culture by 3D. For example, mode 1: taking cells in a liquid cell with liquid Matrigel matrix …… to make the matrix gel solidified… ” (Page 6, 7th para). Also, Hua et al teach “……The inventor unexpectedly found that Rock inhibitor can effectively promote the growth of circulating tumor cells and achieve better enrichment…… adding the Rock inhibitor can further reach the optimization circulating tumor cell culture system. …… obtained number of circulating tumor cells of high purity” (Page 6, 6th para). Hua et al also teach cell culture in 37 degrees centigrade and 5%CO2 (Page 10, 8th para.).
Although Hua et al teach cell culture with 5% CO2 (for the claimed: “carbon dioxide in an amount of less than about 10%”), Hua et al do not teach “oxygen in an amount of less than about 10%”. Lim et al cure the deficiency.
Lim et al teach “cancer cell enrichment system” (title), and “Cell enrichment systems can be used to enrich, isolate, and expand different populations of cells. These cell populations can include, for example, cancer cells, circulating tumor cells, stem cells, and immune cells” ([0003], page 1), and “Example 4: EPCAM Expression of Pancreatic CTC Colonies: To determine EPCAM expression in pancreatic CTC colonies, 6 patients with pancreatic ductal adenocarcinoma (PDAC) were profiled. Apheresed blood samples were collected and cultured to yield CTC colonies” (Example 4, [0152], page 14). Lim et al teach the CTCs cells are grown in hypoxic conditions ([0049], page 4) and “The culturing conditions in a method of the invention can be adjusted to simulate oxygen and pressure levels found in a particular microenvironment to promote the collection of a desired cell population …... The oxygen level used during culturing conditions or in a cell incubator can be, for example, about 0.1 %, about 0.2%, about 0.3%, …. about 1%, …… 25% oxygen in the incubator. In some embodiments, the cells can be grown under hypoxic conditions” ([0072], page 5), and “In some embodiments of a gas flow regulation system, the instructions to regulate to an instructed hypoxic level include instructions to adjust the oxygen level to a value within a range of about 0.1 % to about 21 % oxygen” ([0014], page 2).
Therefore, it would have been prima facie obvious for a person of ordinary skill in the art before the effective filing date of the rejected claims to combine the teachings of prior art to modify the method of Hua et al by culturing circulating tumor cells (CTCs) under hypoxic conditions such as less than 2% O2 as taught by Lim et al as instantly claimed, with a reasonable expectation of success. Said modification amounting to combining prior art elements according to known methods to yield predictable results. One of ordinary skill in the art would have been motivated to do so because Lim et al teach “The culturing condition in a method of the invention can be adjusted to simulate the pressure found in the tumor microenvironment to promote the collection of, for example, CTCs, maintenance of a tumor biopsy, or expansion of a tumor biopsy” ([0073], page 5), and “the selective proliferation of a target cell subpopulation can be evidenced by, for example, a two-fold increase in the proliferation rate of the target primary cell subpopulation as compared to the proliferation rate of the non-target primary cell subpopulation” ([0083], page 6-7). One of ordinary skill in the art would have had a reasonable expectation of success in doing so because Lim et al were successful in isolation and culturing CTC cells with increased proliferative signature such as EPCAM with working example and detailed instructions.
Regarding to claims 9-10, Hua et al teach “the peripheral blood taken from an organism afflicted with cancer, the cancer comprises gastric cancer, intestinal cancer, lung cancer, gallbladder cancer, or pancreatic cancer” (Page 3, 8th para.), and “tumor metastasis is main reason failure caused tumor treatment and tumor patient death. Malignant tumor cell transfer method is mainly 4: direct invasion to surrounding tissues, lymphatic metastasis, blood transfer, drop planting transfer …...” (Page 2, 3rd para.).
Regarding to claim 23, as described above, Hua et al also teach cell culture in 37 degrees centigrade and 5% CO2 (Page 10, 8th para.). Also, Lim et al teach “the CO2 levels in the cell culture incubator can be, for example, …... about 5%, about 4.9% ......” ([0101], page 9).
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Hua et al (CN 109207428 A, Date Published: 2019-01-15) in view of Lim et al (Pub. No.: US 2018/0066223 A1, Pub. Date: Mar. 8, 2018) as applied to claims 8, 9, 10 and 23 above, and further in view of Hughes et al (J. Vis. Exp. (64), e4248, doi:10.3791/4248 (2012)).
The teachings of Hua et al and Lim et al above are incorporated herein in their entirety.
Hua et al and Lim et al do not teach the whole blood sample is collected in a heparinized collection tube. Hughes et al cure the deficiency.
Hughes et al teach “rapid isolation of viable circulating tumor cells from patient blood samples” (Title). Hughes et al teach “ Preparation of samples for cell isolation: Draw or obtain 10 mL blood from patient into heparinized tube” (see page 2, item 4 “Preparation of samples for cell isolation”).
Therefore, it would have been prima facie obvious for a person of ordinary skill in the art before the effective filing date of the rejected claims to combine the teachings of prior art to modify the method of Hua et al and Lim et al above by drawing or obtaining blood from patient into heparinized tube as taught by Hughes et al as instantly claimed, with a reasonable expectation of success. Said modification amounting to combining prior art elements according to known methods to yield predictable results. One of ordinary skill in the art would have been motivated to do so because Hughes et al teach “rapid isolation of viable circulating tumor cells from patient blood samples” (Title). Hughes et al stated that “This device is produced by a straightforward technique using off-the-shelf materials, and has been successfully used to capture cancer cells from the blood of metastatic cancer patients. Captured cells are maintained for up to 15 days in culture following isolation, and these samples typically consist of >50% viable primary cancer cells from each patient. This device has been used to capture viable CTC from both diluted whole blood and buffy coat samples. Ultimately, we present a technique with functionality in a clinical setting to develop personalized cancer therapies.” (Abstract). One of ordinary skill in the art would have had a reasonable expectation of success in doing so because Hughes et al were successful in rapidly isolation of cancer cells from the blood of metastatic cancer patients with detailed instructions, working examples and protocol.
Claims 17 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Hua et al (CN 109207428 A, Date Published: 2019-01-15) in view of Lim et al (Pub. No.: US 2018/0066223 A1, Pub. Date: Mar. 8, 2018) as applied to claims 8, 9, 10 and 23 above, and further in view of Zhang et al (Pub. No .: US 2021/0189351 A1, Provisional application No. 62/720,010 , filed on Aug. 20, 2018).
The teachings of Hua et al and Lim et al above are incorporated herein in their entirety.
Hua et al and Lim et al do not teach “three-dimensional cell culture comprises a culture vessel that inhibits attachment of the cells to the vessel surface” (claim 17), and “the three-dimensional cell culture further comprises transferrin, insulin, and putrescine” (claim 20). Zhang et al cure the deficiency.
Regarding to claim 17, Zhang et al teach “The technology relates in part to epithelial cell spheroids and methods of producing epithelial cell spheroids” (Abstract), and “in certain embodiments , diseased epithelial cells may include cells isolated from circulation (e.g. , circulating tumor cells (CTCs) of a subject” ([0046], page 5). Zhang et al teach “Spheroid inducing culture conditions comprise culturing a cellular aggregate in liquid suspension in a low-attachment container (e.g., ultra-low attachment plate) . In some embodiments, spheroid -inducing culture conditions comprise encapsulating a cellular aggregate in a hydrogel (i.e. , water -infused network of polymers) ….” ([0091], page 13).
Regarding to claim 20, Zhang et al teach “…cells may be seeded into or onto a natural or synthetic three-dimensional cell culture surface. A non-limiting example of a three-dimensional surface is a Matrigel-coated culture surface …” ([0159], page 24), and “additional ingredients may be added to a cell culture medium herein. For example, such additional ingredients may include …… insulin , …... putrescine, …… and transferrin” ([0138], page 21).
Therefore, it would have been prima facie obvious for a person of ordinary skill in the art before the effective filing date of the rejected claims to combine the teachings of prior art to modify the method of Hua et al and Lim et al above by culturing a cellular aggregate such as circulating tumor cells in liquid suspension in a low-attachment container (e.g., ultra-low attachment plate) with cell culture comprising transferrin, insulin, and putrescine as taught by Zhang et al as instantly claimed, with a reasonable expectation of success. Said modification amounting to combining prior art elements according to known methods to yield predictable results. One of ordinary skill in the art would have been motivated to do so because Zhang et al teach that cells or spheroids are encapsulated in hydrogel that generally allows sufficient transport of oxygen, nutrients, metabolic wastes , and secretory products to and from the spheroids to the bulk media, without allowing the cells to leak out of the capsules. Encapsulation may offer efficient protection for the spheroids and may facilitate subsequent downstream processes ([0186], page 28). Zhang et al teach the use of alginate, HyStem-C hydrogel, or Matrigel improved cell survival ([0204], page 30). One of ordinary skill in the art would have had a reasonable expectation of success in doing so because Zhang et al were successful in culturing and improving epithelial cell survival with working examples and data.
Conclusion
No claim is allowed.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/KHOA NHAT TRAN/Examiner, Art Unit 1632
/PETER PARAS JR/Supervisory Patent Examiner, Art Unit 1632
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