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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 3/23/2026 has been entered.
Claims 25-45, of record 3/23/2026, are pending and subject to prosecution. Claims 25, 30, and 38 are amended.
Status of Prior Rejections/Response to Arguments
RE: Rejection of claims 25-26, 29-31, and 34-37 under 35 U.S.C. 103 over Bhatia et al. (WO 2011026221 A1) in view of Eddington et al. (US 20170261496 A1):
RE: Rejection of claims 25-31 and 34-37 under 35 U.S.C. 103 over Bhatia et al. (WO 2011026221 A1) in view of Eddington et al. (US 20170261496 A1), further in view of Okano et al. (US 20220235331 A1):
RE: Rejection of claims 25-26 and 29-37 under 35 U.S.C. 103 over Bhatia et al. (WO 2011026221 A1) in view of Eddington et al. (US 20170261496 A1), further in view of Miyamoto et al. (Journal of Bioscience and Bioengineering, 2016):
The amendment to independent claims 25, 30, and 38 to require an undifferentiated state maintenance medium comprising a factor which acts to maintain the undifferentiated state of the pluripotent stem cell is effective to obviate the rejections. The rejections are withdrawn.
RE: Rejection of claims 25-26 and 29-45 under 35 U.S.C. 103 over Bhatia et al. (WO 2011026221 A1) in view of Eddington et al. (US 20170261496 A1), further in view of Miyamoto et al. (Journal of Bioscience and Bioengineering, 2016), further in view of Spence et al. (Nature, 2010):
The applicant asserts that because the teachings of Bhatia et al., Eddington et al., and Miyamoto et al. pertain to the culturing of cells on a 2D patterned surface, one of ordinary skill in the art would not have combined them with the teachings of Spence et al., which involve embedding pre-formed spheroids in a 3D Matrigel culture system, with any reasonable expectation of success (Applicant Remarks, page 13).
The applicant’s argument is not found persuasive. Bhatia et al. disclose the culture of 3D stem cell aggregates into embryoid bodies on a Matrigel substrate and their subsequent differentiation. Spence et al. teach growth factors for intestinal tissue differentiation of stem cell aggregates and embryoid bodies grown using Matrigel as the substrate. One of ordinary skill in the art, proficient in assays for differentiating stem cells, could therefore apply the teachings of Spence et al. to the method rendered obvious by Bhatia et al. and the supporting references in order to promote differentiation to intestinal tissue with a reasonable expectation of success. The rejection, however, is withdrawn due to the amendment to claims 25, 30, and 38.
New Rejections
Claim Interpretation
Claims 26 and 31 recite the limitation “a region obtained by decomposing or modifying the layer comprising the hydrophilic polymer by plasma treatment, ultraviolet treatment, and/or corona discharge treatment”. The region is described using product-by-process language. Product-by-process limitations are considered only in so far as the method of production imparts distinct structural or chemical characteristics or properties to the product. Therefore, if the product, as claimed, is the same or obvious over a product of the prior art (i.e., is not structurally or chemically distinct), the claim is considered unpatentable over the prior art, even though the prior art product is made by a different process. See MPEP 2113. Because the process of forming the region does not appear to impart any distinct properties to the cell culture substrate, the claimed region is interpreted as a region formed by any means which otherwise meets the limitations of the claims.
Claim Rejections - 35 USC § 103
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 25-26 and 29-37 are rejected under 35 U.S.C. 103 as being unpatentable over Bhatia et al. (WO 2011026221 A1), of record, in view of Bauwens et al. (Stem Cells, 2008), of record in IDS dated 5/15//2023, and Mossahebi-Mohammadi et al. (Frontiers in Cell and Developmental Biology, 2020), evidenced by VanOudenhove et al. (Stem Cells, 2016).
Regarding claims 25-26, 29-31, and 34-37: Bhatia et al. teach methods for generating embryoid bodies that are immobilized to predetermined adhesive locations within cell culture plate wells (See Abstract). An adhesive layer is patterned (which reads on “coating”) onto a non-adhesive surface within the wells, wherein plated cells do not spread to the non-adhesive surface (See ¶0008, 0028, and 0046 and fig. 1). The adhesive regions are shown as being entirely surrounded by non-adhesive regions in fig. 1C (which reads on “(A) an island-shaped region… having cell adhesiveness and cell proliferation” and “(B) a region adjacent to the region (A) and having no cell adhesiveness or having no cell proliferation”). The adhesive layer can include Matrigel, laminin, fibronectin, vitronectin, and collagen (which read on “hydrophilic polymer”) (See ¶0028 and 0046). Multipotent or pluripotent stem cells are plated into wells and cultured under conditions that allow formation of embryoid bodies (See ¶0017). Bhatia et al. teach a general cell differentiation scheme wherein stem cell aggregates are cultured prior to differentiation (which reads on “cultured… in the presence of an undifferentiated state maintenance medium”), exposed to a precursor cell inducing compound (which reads on “a first medium comprising a differentiation-inducing factor”) for the formation of embryoid bodies, then the embryoid bodies are exposed to a progenitor cell inducing compound (which reads on “a second medium comprising a differentiation-inducing factor”) (See ¶0017 and fig. 4). The immobilized embryoid bodies can be cultured under differentiation conditions to prepare a variety of differentiated cells, such as hematopoietic, neural, cardiac, hepatic, or pancreatic cells (See ¶0026 and 0041). The embryoid bodies can be cultured with FGF2, retinoic acid, Noggin, N-2, or B-27 (which read on “differentiation-inducing factor”) in order to produce neural cells (which read on “ectodermal cell aggregate” and “a neural stem cell or a nerve cell”) (See ¶0026). In an example, embryoid bodies triggered to form from the stem cell aggregates are cultured under hematopoietic differentiation conditions with factors including BMP4 (which reads on “bone morphogenetic protein”), SCF, Flt3L, IL-3, IL-6, and G-CSF (which read on “mesoderm-inducing factor”) (See ¶0025, 0042, and 0046). The differentiated embryoid bodies comprised cells positive for CD34 and CD45 (which read on “a mesoderm marker”) (See fig. 2-3).
Bhatia et al. do not expressly teach the area of the adhesive region or the inclusion of a factor to maintain the undifferentiated state of the pluripotent stem cells.
Bauwens et al. teach embryoid body formation through the culture of hESCs on micropatterned Matrigel (See Abstract and fig. 1). Micropatterned Matrigel spots were 200, 400, or 800 µm in diameter (which correspond to areas of 0.031 mm2, 0.12 mm2, and 0.503 mm2 and read on “an area of 0.001 to 5 mm2” (See page 2302, col. 1, ¶1). Colonies were formed by seeding hESCs on the patterns in medium supplemented with FGF2 and TGFβ-1 (See page 2302, col. 1, ¶1).
Mossahebi-Mohammadi et al. teach that FGF2 and TGFβ support stemness in pluripotent cells (See fig. 1).
It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to modify the method of Bhatia et al. to comprise the use of patterned 200, 400, or 800 µm Matrigel spots for generating pluripotent stem cell aggregates for embryoid bodies. One would have been motivated to make this modification because Bauwens et al. teach that embryoid bodies can be formed from size-constrained stem cell aggregates and that a 200, 400, or 800 µm spot can be employed in order to promote endoderm or mesoderm induction for influencing differentiation trajectories (See page 2306, col. 2, full ¶1 and fig. 2). There would be a reasonable expectation of success in doing so because the adhesive regions taught by Bhatia et al. could readily be sized to 200, 400, or 800 µm.
It also would have been obvious to modify the method of Bhatia et al. to include FGF2 and TGFβ-1 in the stem cell medium, as taught by Bauwens et al. One would have been motivated to make this modification because Mossahebi-Mohammadi et al. teach these additives as promoting pluripotency and stemness (See fig. 1), and they could be readily added to culture media.
Regarding claim 32: Following the discussion of claims 25-26, 29-31, and 33-37, Bhatia et al., modified by Bauwens et al. and Mossahebi-Mohammadi et al., render obvious a method of generating differentiated cell aggregates from embryoid bodies but do not expressly teach seeding densities. However, Bauwens et al. teach that the colonies of hESCs seeded on patterned Matrigel spots for generating embryoid bodies comprised approximately 250, 500, and 4500 cells at 2 or 3 days post-seeding on 200, 400, and 800 µm patterned spots, respectively (which corresponds to approximately 8 × 105 cells/cm2, 4 × 105 cells/cm2, and 9 × 105 cells/cm2) (See page 2302, col. 1, ¶1 and fig. 4B). VanOudenhove et al. teach that hESCs grown under pluripotent conditions have a doubling time of approximately 17 h (See fig. 1A). Given that approximately 3-4 doublings can take place in the span of 2-3 days, the density of the seeded cells on the patterned spots would have fallen into the claimed range of 1.0 × 102 to 1.0 × 106 cells/cm2.
Regarding claim 33: Following the discussion of claims 25-26, 29-31, and 34-37, Bhatia et al. do not expressly teach an ending cell density for the embryoid bodies.
However, Bauwens et al. teach embryoid bodies comprising approximately 200, 300, and 4000 cells initially formed from 200, 400, and 800 µm patterned spots, respectively (which corresponds to approximately 6.4 × 104 cells/cm 2, 2.5 × 105 cells/cm2, and 8 × 105 cells/cm2 and reads on “1.0 × 104 cells/cm2 or more”) (See fig. 4B), indicating that the use of adherent areas of those sizes for forming stem cell aggregates will yield embryoid bodies that read on the claimed invention.
Claims 25-37 are rejected under 35 U.S.C. 103 as being unpatentable over Bhatia et al. (WO 2011026221 A1), of record, in view of Bauwens et al. (Stem Cells, 2008), of record, and Mossahebi-Mohammadi et al. (Frontiers in Cell and Developmental Biology, 2020), evidenced by VanOudenhove et al. (Stem Cells, 2016), further in view of Okano et al. (US 20220235331 A1), of record.
The teachings of Bhatia et al., Bauwens et al., Mossahebi-Mohammadi et al., and VanOudenhove et al. are set forth in the rejections above and are incorporated herein in their entirety.
Regarding claims 27-28: Following the discussion of claims 25-26 and 29-37, Bhatia et al., modified by Bauwens et al. and Mossahebi-Mohammadi et al., evidenced by VanOudenhove et al., render obvious a method of generating differentiated cell aggregates from embryoid bodies but do not expressly teach the inclusion of specific differentiation factors for ectoderm, mesoderm, and endoderm.
Okano et al. teach methods for obtaining neural stem cell-like cells from induced pluripotent stem cells (See Abstract). The neural induction medium comprised the TGF-β inhibitor A83-01, the MAP kinase inhibitor PD0325901 (which reads on “ectoderm-inducing factor”) and CHIR99021 (which reads on “mesoderm-inducing factor” and “endoderm-inducing factor”) (See ¶0181-0182). The resulting cell aggregates comprise ectoderm, mesoderm, and endoderm and express PAX6 and SOX1 (See ¶0206 and 0244-0246 and fig. 16 and 39-41).
It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to modify the method of Bhatia et al., modified by Bauwens et al. and Mossahebi-Mohammadi et al., evidenced by VanOudenhove et al., to comprise the neural induction medium taught by Okano et al. One would be motivated to make this modification because that it can be used for generating neural lineage cells from pluripotent stem cell colonies (See fig. 39-41). There would be a reasonable expectation of success in doing so because Bhatia et al. teach that the embryoid bodies can be differentiated to neural cells (See ¶0041).
Claims 25-26 and 29-45 are rejected under 35 U.S.C. 103 as being unpatentable over Bhatia et al. (WO 2011026221 A1), of record, in view of Bauwens et al. (Stem Cells, 2008), of record, and Mossahebi-Mohammadi et al. (Frontiers in Cell and Developmental Biology, 2020), evidenced by VanOudenhove et al. (Stem Cells, 2016), further in view of Spence et al. (Nature, 2010), of record.
The teachings of Bhatia et al., Bauwens et al., Mossahebi-Mohammadi et al., and VanOudenhove et al. are set forth in the rejections above and are incorporated herein in their entirety.
Regarding claims 38-45: Following the discussion of claims 25-26 and 29-37, Bhatia et al., modified by Bauwens et al. and Mossahebi-Mohammadi et al., evidenced by VanOudenhove et al., render obvious a method of generating differentiated cell aggregates from embryoid bodies comprising specific cell numbers but do not expressly teach the cells as intestinal cells.
Spence et al. teach the in vitro differentiation of pluripotent stem cells to intestinal tissue organoids (which read on “endodermal cell aggregate”) (See Abstract). Pluripotent stem cell aggregates that had been treated with activin A were attached to Matrigel containing R-Spondin-1, Noggin (which reads on “TGF-β inhibitor”), and EGF and cultured in media comprising N-2 and B-27 (which all read on “differentiation-inducing factor”) (See page 110, col. 1, ¶1-3 and fig. S1). The resulting spheroids (which reads on “hemispherical shape”) comprised intestinal epithelial cells and showed expression of SOX17 and villin (which reads on “VIL1”) (See fig. S1-S2, S7-8, and S11).
It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to modify the method of Bhatia et al., modified by Bauwens et al. and Mossahebi-Mohammadi et al., evidenced by VanOudenhove et al., to comprise differentiation to intestinal cells, such as is taught by Spence et al. One would be motivated to make this modification because Spence et al. teach that intestinal cell organoids can be used for functional studies, drug design, and eventual transplantation therapy (See page 108, col. 1, full ¶2). There would be a reasonable expectation of success in doing so because Bhatia et al. teach that embryoid bodies can be further differentiated to an unlimited variety of cell types (See ¶0041) and because Spence et al. teach specific culture additives that can be used to promote intestinal tissue differentiation from pluripotent cell aggregates (See page 110, col. 1, ¶1-3 and fig. S1).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JENNIFER S SPENCE, whose telephone number is 571-272-8590. The examiner can normally be reached M-F 8:30-5:30.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Christopher M Babic, can be reached at 571-272-8507. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JENNIFER S SPENCE/Examiner, Art Unit 1633
Prosecution Insights