AMOLIFESCIENCE CO., LTD.

Patent Trials and Appeals Board

Mar 1, 2022

2021003164 (P.T.A.B. Mar. 1, 2022)

UNITED STATES PATENT AND TRADEMARK OFFICE UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 15/559,237 09/18/2017 In Yong SEO JLE0176US 3962 23413 7590 03/01/2022 CANTOR COLBURN LLP 20 Church Street 22nd Floor Hartford, CT 06103 EXAMINER CLARKE, TRENT R ART UNIT PAPER NUMBER 1651 NOTIFICATION DATE DELIVERY MODE 03/01/2022 ELECTRONIC Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address(es): usptopatentmail@cantorcolburn.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte IN YONG SEO, SEUNG HOON LEE, SONG HEE KOO, and JI HYUN LEE Appeal 2021-003164 Application 15/559,237 Technology Center 1600 BEFORE JEFFREY N. FREDMAN, JOHN E. SCHNEIDER, and RACHEL H. TOWNSEND, Administrative Patent Judges. SCHNEIDER, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the Examiner’s decision to reject claims 12 and 14. We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM. 1 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R. § 1.42(a). Appellant identifies the real party in interest as AMOLIFESCIENCE CO., LTD. Appeal Br. 3. Appeal 2021-003164 Application 15/559,237 2 CLAIMED SUBJECT MATTER The claims are directed to a cell support structure comprising a water- soluble polymer, “which can elute cells to be grown, maximize a survival rate of cells by providing a culture environment familiar to cell culture, and grow cells in a desired shape and skeleton.” Spec. ¶ 1. Claim 12, reproduced below, is illustrative of the claimed subject matter: 12. A cell culture support using a water-soluble polymer, the cell culture support comprising: a first fibrous web having first pores and formed of accumulated electrospun first fibers, the first fibers being formed of a first water-soluble polymer and a first synthetic polymer, wherein first beads are formed on the first fibers to form spaces of the first pores; a second fibrous web laminated on the first fibrous web, the second fibrous web having second pores and formed of accumulated electrospun second fibers, the second fibers being formed of a second water-soluble polymer and a second synthetic polymer, wherein second beads are formed on the second fibers to form spaces of the second pores; and a third fibrous web laminated on the second fibrous web, the third fibrous web having third pores and formed of accumulated electrospun third fibers, the third fibers being formed of a third water-soluble polymer and a third synthetic polymer, wherein third beads are formed on the third fibers to form spaces of the third pores, wherein the first, second and third water-soluble polymers are a mixture of two or more selected from the group consisting of PVA (polyvinyl alcohol), PVP (polyvinyl pyrrolidone), polyethylene oxide (PEO), carboxyl methyl cellulose (CMC), starch, polyacrylic acid (PAA), and hyaluronic acid, wherein the accumulated electrospun first, second and third fibers are obtained by electrospinning a spinning solution having a viscosity from 50 cps to 2000 cps, wherein the third fibrous web is configured to culture cells adhered to the third fibers, and the second fibrous web is Appeal 2021-003164 Application 15/559,237 3 configured to grow the cells penetrated into the spaces of the second pores, wherein the third fibers have a diameter smaller than that of the second fibers to increase a surface area to which the cells are adhered, and wherein the first fibers have a diameter smaller than that of the second fibers to prevent grown cell to penetrate into the first fibrous web from the second fibrous web. REFERENCES The prior art relied upon by the Examiner is: Name Reference Date Aun Wan, et al. US 2007/0020244 A1 Jan. 25, 2007 Chong, et al. US 2009/0202616 A1 Aug. 13, 2009 Pham et al., Electrospun Poly(ε-caprolactone) Microfiber and Multilayer Nanofiber/Microfiber Scaffolds: Characterization of Scaffolds and Measurement of Cellular Infiltration, 7 Biomacromolecules 2796 (2006) REJECTION The Examiner has rejected claims 12 and 14 under 35 U.S.C. § 103 as unpatentable over Chong in view of Aun Wan and Pham. OPINION The issue before us is whether a preponderance of the evidence supports the Examiner’s conclusion that the subject matter of claims 12 and 14 would have been obvious to one of ordinary skill in the art at the time the invention was made over Chong combined with Aun Wan and Pham. The Examiner finds Chong teaches a cell support structure comprising water-soluble polymers which form a fibrous web. Final Act. 3. The polymer used to prepare the fibers include collagen, gelatin, keratin, chitosan, polypeptides, proteins, poly-e-caprolactone, polyethylene oxide, Appeal 2021-003164 Application 15/559,237 4 polyvinyl alcohol, polyvinyl pyrrolidone, polyamide, polylactic acid, and mixtures thereof. Id. at 3-4. The Examiner finds Chong does not teach the support comprises beads formed on the fibers, but finds Aun Wan teaches this element of the claims. Id. at 4. The Examiner finds “Aun Wan teaches fiber compositions for tissue engineering (i.e. cell culture supports) wherein the supports comprise beads formed on the fibers ([0012], Fig. 6) wherein the beads are comprised of the fiber forming material [0005] and wherein the beads are 2 - 25 times greater in diameter than the fibers of the support and provide bioactive materials for the cells.” Id. The Examiner concludes a person of ordinary skill in the art at the time of filing would have found it obvious to produce the cell culture support made obvious by Chong wherein the support comprises a plurality of beads formed on the fibers wherein the diameters of the beads are larger than the diameters of the fibers because Aun Wan teaches supports with beads formed on the fibers which are 2 - 25 times greater in diameter than the fibers of the support for providing bioactive materials to the cells. Id. The Examiner finds Chong does not teach a scaffold comprising three layers but finds “a person of ordinary skill in the art at the time of filing would have found it obvious to produce a cell culture support comprising three layers of fibrous web because Pham teaches multilayer fibrous webs produced by sequentially electrospinning the fibrous webs onto the preceding layer, i.e. laminating the web on the previous layer.” Id. at 5. The Examiner finds Pham teaches that the top surface layer (corresponding to the claimed third layer which being the top surface of the scaffold is configured to culture cells) is produced with 600 nm fibers (called nanofibers in Pham), the second layer down from the Appeal 2021-003164 Application 15/559,237 5 outer surface (corresponding to the claimed second layer) is produced with 5 μm fibers (called microfibers in Pham) and the third layer down from the top surface (corresponding to the claimed first layer) is produced with 600 nm nanofibers (p. 2802, “Fabrication and Characterization of Multilayered Scaffolds.”; Fig. 8), i.e. the multilayer cell culture support taught by Pham comprises a first fibrous web (third layer down from outer surface in Pham) having first pores and formed of accumulated electrospun first fibers, a second fibrous web (penultimate layer in Pham) laminated on the first fibrous web, the second fibrous web having second pores and formed of accumulated electrospun second fibers, and a third fibrous web (topmost web in Pham) laminated on the second fibrous web, the third fibrous web having third pores and formed of accumulated electrospun third fibers, wherein the third fibrous web (outer surface of scaffold in Pham) is configured to culture cells adhered to the third fibers. Hence, a person of ordinary skill in the art at the time of filing would have found it obvious to produce the same multilayered structure taught by Pham with the fibrous webs comprising pores and beads made obvious by Chong in view of Aun Wan; therefore, claim 12 is prima facie obvious. Id. at 5-6. Appellant contends Pham does not teach the recited three-layer structure where the diameter of the fibers in the outer layers is greater than the diameter of the fibers in the inner layer. Appeal Br. 12. Appellant argues Pham teaches a bilayer structure. Id. at 15. Appellant contends Pham teaches away from the claimed arrangement. Id. at 12. Appellant contends that one skilled in the art would not have the motivation to modify Pham to create the recited structure. Id. at 13. We adopt the Examiner’s findings of fact, reasoning on scope and content of the prior art, and conclusions set out in the Final Action and Appeal 2021-003164 Application 15/559,237 6 Answer regarding this rejection. We find the Examiner has established a prima facie showing that the subject matter of the claims would have been obvious over Chong combined with Aun Wan and Pham to a person of ordinary skill in the art at the time the invention was made. Appellant has not produced evidence showing, or persuasively argued, that the Examiner’s determinations on obviousness are incorrect. Only those arguments made by Appellant in the Briefs have been considered in this Decision. Arguments not presented in the Briefs are waived. See 37 C.F.R. § 41.37(c)(1)(iv) (2015). We have identified claim 12 as representative; therefore, all claims fall with claim 12. We address Appellant’s arguments below. Appellant contends that Pham teaches a bilayer structure not a three-layer structure as recited in the claims. Appeal Br. 12, 15. We are not persuaded by this argument. As the Examiner points out, the claims use the transitional phrase “comprising.” Ans. 13. Thus, while the structure must have at least three layers, it does not exclude structures having more than three layers. See Genentech, Inc. v. Chiron Corp., 112 F.3d 495, 501 (Fed. Cir. 1997) (“‘Comprising’ is a term of art used in claim language which means that the named elements are essential, but other elements may be added and still form a construct within the scope of the claim.”). Pham specifically teaches a scaffold structure comprising a nano- micro-nano-micro-nano-microfiber series of layers with the nano fibers having a diameter of 600 nm and the microfibers having a diameter of 5µm. Pham, 2801-2802, Fig. 8. We agree with the Examiner that the five-layer structure taught by Pham meets the limitation of claim 12 calling for the fibers in the first and third layers to have a narrower diameter than the second or middle layer. Ans. 13. Appeal 2021-003164 Application 15/559,237 7 Appellant contends Pham teaches away from the claimed arrangement of fiber layers. Appeal Br. 12, 22. Appellant offers no specific explanation as to how Pham teaches away from a support comprising a three-layer structure wherein the first and third layers have diameters smaller than the fibers in the second or middle layer. We are not persuaded by this argument. As discussed above, Pham specifically teaches a five-layer structure wherein the fibers in three of the five layers have the recited differences in fiber diameter. Moreover, Appellant has not pointed to, nor do we discern any teaching in Pham that criticizes, discredits, or otherwise discourages the development of a support comprising the claimed three-layer structure as recited in claims 12 and 14. See In re Fulton, 391 F.3d 1195, 1201 (Fed. Cir. 2004). Appellant contends there is no reason and motivation in the cited references to prepare a scaffold structure as recited in the claims. Appeal Br. 13, 22. Again we are unpersuaded by this argument. Pham teaches: The scaffold design presented herein integrates nanofibers and microfibers (both produced from electrospinning PCL) to form a single scaffold. As we have demonstrated, the thickness and coverage of the nanofiber layers can be controlled by modulating the electrospinning time of the nanofibers. Furthermore, the number, location, and spacing of the nanofiber layers could also be manipulated. Scaffolds containing different densities of nanofiber layers were used as model systems for investigating the cell infiltration into micro- and nanofiber scaffolds. Doing so provides critical information for the design of scaffolds to optimize the nanofiber (ECM scale mimic) and microfiber (allows for cell infiltration) balance. Appeal 2021-003164 Application 15/559,237 8 Pham, 2802. We agree with the Examiner that Pham provides the motivation to modify Chong to produce the claimed scaffolds. Ans. 12. With respect to the motivation to combined Chong with Aun Wan, we agree with the Examiner that it would be obvious to modify the method of Chong to produce beads on the fibers which make up the layers because the beads on the fibers taught by Aun Wan provide spaces in the layers wherein cells can penetrate into the fibrous web and grow therein as evidenced by Aun Wan and the beads can provide bioactive materials for the cells as taught by Aun Wan. Regarding combining the method made obvious by Chong and Aun Wan with Pham, Chong teaches that the cell culture support can comprise multiple scaffold fiber layers wherein each of the different layers laminated on top of each other can comprise macro, micro or nano fibers, that the thickness of the different layers can be adjusted depending upon the application and teaches that the scaffold fiber layers are capable of supporting cell attachment and proliferation but doesn’t give any specific embodiments; however, a person of ordinary skill in the art at the time of filing would have found it obvious to use the specific layers and fiber diameters of Pham to supplement Chong’s teachings because Pham successfully produces multilayered cell culture scaffolds. Ans. 15-16. Based on the foregoing, we conclude that a preponderance of the evidence supports the Examiner’s conclusion that the subject matter of claims 12 and 14 would have been obvious to one of ordinary skill in the art at the time the invention was made over Chong combined with Aun Wan and Pham. CONCLUSION The Examiner’s rejection of claims 12 and 14 under 35 U.S.C. § 103 as unpatentable over Chong in view of Aun and Pham is affirmed. Appeal 2021-003164 Application 15/559,237 9 DECISION SUMMARY In summary: Claims Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed 12, 14 103 Chong, Aun Wan, Pham 12, 14 TIME PERIOD FOR RESPONSE No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R. § 1.136(a)(1)(iv). AFFIRMED