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 .
DETAILED ACTION
This application is a US national phase of PCT/US14/43624, filed June 23, 2014, a DIV of 14/899394, filed December 17, 2015, and has a provisional application 61/838452, filed June 24, 2013. Applicant’s amendment filed October 28, 2025 is acknowledged. Claims 1-9 and 15-16 are canceled, and claim 10 is amended. Currently claims 10-14 and 17-18 are pending and under examination.
The previous 112(b) rejection in the Non-Final office action mailed July 28, 2025 is withdrawn due to Applicant’s amendment to the claims filed October 28, 2025.
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.
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 10-14 and 17-18 are rejected under 35 U.S.C. 103 as being unpatentable over Pliszczak et al. (European Journal of Pharmaceutical Sciences 44 (2011) 83–92, cited in PTO-892 filed 7/1/2024, hereinafter “Pliszczak”) in view of Tabata (US 2012/0225483 A1, cited in PTO-892 filed 12/11/2024), Poncelet (Annals NY Academy of Sciences, 2001, 944:74-82, cited in PTO-892 filed 12/11/2024), Martin et al. (US 2011/0183418 A1, cited in PTO-892 filed 12/11/2024, hereinafter “Martin”), Schneider et al. (Enzyme and Microbial Technology 48 (2011) 312–318, cited in PTO-892 filed 7/1/2024, hereinafter “Schneider”), Braschler et al. (Lab Chip, 2005, 5, 553–559, cited in PTO-892 filed 7/1/2024, hereinafter “Braschler”), and
Pliszczak teaches bioadhesive microparticles comprising low methylated pectin (a form of polygalacturonic acid), calcium chloride (CaCl2), and hyaluronic acid (HA) (title, pg. 84, sec. 2.2). Pliszczak teaches as alginate, low methyl pectin (LM pectin) forms a gel in contact with divalent cations such as Ca2+ ions (a cross-linking agent), and is further associated with HA (a biopolymer) to promote bioadhesive properties (abstract, pg. 84, col. 1, para 3). As evidenced by the Specification, low methoxyl pectin (LM pectin) has a degree of methylation (esterified) of typically 1-40 mol% which meets the limitation of claims 10 and 14 (para 65). Pliszczak teaches one of the most common methods used for probiotic encapsulation is based on the gelation of alginate in contact with calcium ions (pg. 84, col. 1, para 2). The microparticles/microbeads (a form of microcarrier) were loaded with probiotic bacteria and evaluated for their bioadhesiveness, which meets the limitation of claims 10, 14, and 17 (pg. 84, sec. 2.2). Pliszczak teaches Ca2 ion amount in the pectin/HA beads was determined by ethylene diaminetetraacetic acid (EDTA) titration and teaches EDTA is a chelating agent complexing with most metal ions which meets the limitation of claims 10 and 12 (pg. 84, sec. 2.4). Pliszczak teaches the in-vitro release of the probiotic from the complexed microparticles was achieved in simulated vaginal fluid at pH 4.2 comprising porcine gastric mucin (type II), inter alia (pg. 85, sec. 2.6.3, Table 1). Pliszczak teaches after incubation time of 30 min, samples were filtered in order to recuperate a bacterial solution and enumerate the released probiotic bacteria, which meets the limitation of claims 10 and 11 (pg. pg. 85, sec. 2.6.3). Pliszczak also does not include protease in the method of releasing the bacterial cells, thus inherently meets the limitation of claim 13.
Even though Pliszczak does not explicitly teach the culturing of cells to the microbeads, but rather encapsulation of the live bacteria, Tabata teaches microspheres for cell culture that include a hydrogel in which water-soluble synthetic polymers, including polyacrylamide, polyacrylic acid, poly hydroxyethyl methacrylate, and polyvinyl alcohol, polysaccharides (such as pectin), and/or proteins are subjected to chemical cross linking (title, abstract, para 24). Thus, it would be obvious to one of ordinary skill in the art to utilize the controlled release bioadhesive microparticles taught by Pliszczak for a cell culture article utilizing chemically modified pectin as taught by Tabata [0011].
Pliszczak does not explicitly teach the microcarriers are internally gelated and a bead with a size ranging from 0.01 microns to 0.5 microns. However, Tabata teaches the average microsphere size of the resulting gelation hydrogel microspheres depends on gelation concentration at the time of preparation, a volume ratio of a gelation solution, and a stirring rate, and in general range from 500nm to 1000µm (para 28). Tabata teaches further pre-emulsification can produce microparticulate gelatin hydrogel microspheres having a size of microsphere of 50nm to 20µm (para 28). Tabata teaches the preferable microsphere size is about 50nm to 1000µm, which overlaps with the claimed size range recited in claims 10 and 18. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
Although Pliszczak and Tabata do not explicitly teach the microbead is internally gelated, Poncelet teaches it was well known at the time of filing to utilize internal gelation to produce microcarrier particles. (Abstract). One of ordinary skill in the art would have been motivated to utilize an internally gelated particle in the cell culture article taught by Pliszczak and Tabata, because Poncelet further teaches internal gelation advantageously "form[s] beads in a large scale, under sterile conditions with a relatively low mean size." (Page 82, conclusions).
Tabata also teaches in order to further enhance cell culture and proliferation, the microsphere surface can be coated or immobilized with a cell adhesion peptide and a cell adhesion protein such as collagen, fibronectin, vitronectin, laminin, and glycosaminoglycan (para 24). Neither Pliszczak nor Tabata teach the adhesion polymer comprises a conjugated polypeptide with at least one poly(MAA-PEG4-VN) homopolymer or poly(HEMA-co-MAA-PEG4-VN) copolymer, wherein MAA is methacrylic acid, HEMA is hydroxyethylmethacrylate, PEG4 is polyethylene glycol tetra oligomer, and VN is a conjugated vitronectin.
However, Martin teaches peptide-polymer cell culture articles and methods of making (title). Martin teaches peptide mimetic cell culture surfaces or coatings prepared by free radical polymerization of acrylate or methacrylate functionalized cell adhesive peptides with hydrophilic acrylate or methacrylate monomers and cross-linkers (para 17). Martin teaches adhesion polymer formulations, such as HEMA-MAA-PEG4-VN, which meets the limitation of claims 10 and 14 (pg. 7, Table 5).
Pliszczak, Tabata, and Martin do not explicitly teach the use of a mixture of pectinase and EDTA (chelator) to separate the cells from the gelled microparticles.
However, Schneider teaches bioresponsive systems based on polygalacturonate containing hydrogels (PSA consisting of alginic acid and polygalacturonic acid) complexed with CaCl2 (PSA-CaCl2) (title, abstract). Schneider teaches the PSA-CaCl2 beads were loaded with Alizarin as a model ingredient and subjected to trigger enzymes (polygalacturonase or pectate lyase) and found a linear relation between the release of Alizarin and enzymatic activity (abstract). Schneider teaches polygalacturonate can be cleaved by enzymes such as pectinases and polygalacturonase (pg. 313, col. 1, para 2). Alizarin as a model ingredient was incorporated into polygalacturonate based devices to study enzyme triggered release and upon pH change from neutral up to pH 10 Alizarin changes its color from lightly orange to dark violet which can be used for signal enhancement (pg. 313, col. 1, para 3). Schneider teaches the backbone of polygalacturonate consists of galacturonic acid units with partly free and esterified carboxylic groups, and can be used in cross-linking and blended with related polysaccharides such as alginates (pg. 312, col. 2, para 2). Schneider teaches glycidyl methacrylate (GMA) was used to form a cross-linked PSA-GMA hydrogel and found no significant release of dye from the blank while after 2.5 h, Alizarin were released upon incubation with 50 U ml−1 pectinase which meets the limitation of claim 10 (pg. 314, col. 2, para 6).
Braschler also teaches gentle cell trapping release by in situ alginate hydrogel formation (title). Braschler teaches cell entrapment is based on the controlled formation of an alginate hydrogel by bringing two laminar flows of alginate and calcium ions, and adding EDTA to the alginate solution allows for control of the hydrogel growth, and by varying the ratio of Ca2+ to EDTA concentrations gel growth or gel shrinkage can be induced at will, thus trapped cells are released during shrinkage of the gel which meets the limitations of claims 10-12 (abstract).
Therefore, it would have been prima facie obvious to one of ordinary skill in the art at the time of filing to utilize the bioadhesive PGA substrate/pectin/HA beads for adhesion of cells taught by Pliszczak for creating a cell culture article that is an internally gelated microbeads/microcarriers in the size range between 500nm-1000µm as taught by Tabata and Poncelet, and the incorporated adhesion polymer on the surface of the substrate is poly(MAA-PEG4-VN) as taught by Martin with a reasonable expectation of success. One of ordinary skill in the art would have been motivated to coat the microbeads/microcarriers with conjugated methacrylate polymers and vitronectin, as these adhesion coatings create a peptide mimetic surface that is scalable, easy to process, cost effective and can facilitate the growth and proliferation of difficult to culture cells as taught by Martin (para 17).
Further, one of ordinary skill in the art would have been motivated to utilize the methods of releasing the cells by applying pectinase taught by Schneider and EDTA taught by Pliszczak and Braschler with a reasonable expectation of success. One of ordinary skill in the art would have been motivated to combine a pectinase which has inherent polygalacturonate degrading ability which would affect the stability and structure of the substrate (hydrogel) with EDTA that naturally chelates with Ca2 ions and causes gel shrinkage that releases trapped cells, thus advantageously releasing the cultured cells from the substrate with a reasonable expectation of success. By utilizing both pectinase and EDTA, the polygalacturonic acid hydrogel would be dually destabilized by the chelating of the calcium ions and the enzymatic cleavage of the polygalacturonate, and thus the cultured cells would be released.
Response to Arguments
Applicant's arguments filed October 28, 2025 have been fully considered but they are not persuasive.
Regarding the rejection under 35 U.S.C. §103, Applicant argues no prima facie case of obviousness exists over the presently amended claims. None of the cited references teach culturing cells on an internally gelated PGA-based substrate having a PEG-based conjugated polypeptide adhesion polymer coating, and then harvesting the cells with a non-proteolytic enzyme and chelator to dissolve the substrate and free the cultured cells. It is this combination that is claimed. The Examiner's addition of Poncelet as a cited reference, an alginate-based substrate that solely discusses the mechanical attributes of alginate-based beads, does not teach or suggest the above combination, alone or in combination with the five other cited references.
In response to applicant’s argument that there is no teaching, suggestion, or motivation to combine the references, the examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007). In this case, Pliszczak teaches the LM pectin’s bioadhesiveness and ability to release cells when coming into contact with EDTA or vaginal fluid. Although Pliszczak teaches the cells are encapsulated instead of cultured on the surface, Tabata teaches cell culture articles as microbeads that form aggregates that can comprise pectin and coatings on the surface to further enhance cell culture or proliferation [0024]. Poncelet teaches internal gelation techniques for various polysaccharides that are well known in the art. Martin teaches the particular surface coatings poly(MAA-PEG4-VN), and Pliszczak, Schneider, and Braschler teach the cell release method of utilizing pectinase and EDTA.
Applicant further argues the uncertainty that the cells would grow on alginate versus PGA, and if they are externally or internally gelated is seen in Examples 2 & 8, which show these formulations do not support cell growth. Applicant submits that the Examiner’s statement of motivation to combine are indicative of arriving at the specific combination claimed stemming from knowledge of the claimed invention itself-which is hindsight. See e.g., In re Dance, 160 F.3d 1339, 1343 (Fed. Cir. 1998).
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). Although Pliszczak does not explicitly teach the method includes internally gelating the microbeads, Poncelet teaches internal and external gelation methods are well-known in the art, and one of ordinary skill in the art would predictably adjust the gelation technique for one’s intended purpose, such as controlling beads size and egress permeability with large molecules as taught by Poncelet (pg. 74, para 2; pg. 79, para 3). Thus it would be well within the wheel-house for one of ordinary skill in the art to modify the gelation technique for an intended purpose of adjusting the microbead size to develop a cell culture article as taught by Poncelet and Tabata based on the teachings of Poncelet, and coat the culture article with poly(MAA-PEG4-VN) taught by Martin, and finally utilize the cell culture trapping and release methods taught by Poncelet, Schneider, and Braschler with a reasonable expectation of success.
Conclusion
THIS ACTION IS MADE FINAL. 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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JESSICA EDWARDS whose telephone number is (571)270-0938. The examiner can normally be reached M-F 8am-5pm EST.
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/LOUISE W HUMPHREY/Supervisory Patent Examiner, Art Unit 1657
/JESSICA EDWARDS/
Examiner, Art Unit 1657