DETAILED ACTION
This action is in reply to papers filed 05/02/2026.
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 .
Status of Claims
Claims 1-3 and 6-14 are pending and examined herein.
Claims 1 and 8 are currently amended.
Claims 4-5 and 15-20 are cancelled.
Withdrawn Rejections
The cancellation of claims 4-5 and 15 renders any rejections thereof moot.
The rejection of claim 8 under an improper Markush grouping is withdrawn in light of the amendment to claim 8.
The rejection of claims 1-3 under 35 U.S.C. 102(a)(1) as being anticipated by Mariassy (Experimental Lung Research, 1983, 4(4): 293-314) is withdrawn in light of the amendment to claim 1 to specify the order of steps in the method recited therein.
Applicant’s arguments regarding the rejection of claims 1-3 under 35 U.S.C. 102(a)(1) and claims 1-14 under 35 USC 103 and the prior art cited therein are addressed following the maintained rejections.
Claim Objections
Claim 1 objected to because of the following informalities: Amended claim 1 recites the phrase “the method comprising the steps of, in the following order” (lines 1-2), which should be corrected to “the method comprising steps in the following order” or its equivalent. Appropriate correction is required.
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.
Claim(s) 1-3 are rejected under 35 U.S.C. 103 as being unpatentable over Mariassy (Experimental Lung Research, 1983, 4(4): 293-314).
Claims 1-3 were previously rejected under 35 U.S.C. 102(a)(1) as being anticipated by Mariassy. This is a new ground of rejection, necessitated by the amendment to claim 1 to specify the order of steps in the method recited therein.
Mariassy teaches a method of processing parietal tissue from sheep for microscopy (Abstract). Mariassy discloses euthanizing sheep (claims 2-3), then removing the lungs (acquiring a tissue, claim 1) and fixing the lungs by tracheal infusion using Karnosky’s fixative (p 294, para 1). The parietal pleura was fixed by immersion (p 294, para 1) (claim 1). Following overnight fixation, the parietal pleura was taken from the mediastinal regions (p 294, para 2) (selecting a sample of mediastinal pleura tissue, claim 1).
With respect to the order of steps in claim 1, it is noted that the courts have held that any order of performing process steps is prima facie obvious in the absence of new or unexpected results (In re Gibson, 39 F.2d 975, 5 USPQ 230 (CCPA 1930); Ex parte Rubin, 128 USPQ 440 (Bd. App. 1959)). See MPEP §2144.04 (IV)(C). Therefore, the claimed order of steps is an obvious variant of the steps of the cited prior art.
Claim(s) 1-3 and 6-14 remain rejected under 35 U.S.C. 103 as being unpatentable over Kassab (WO 2013/120082 A1), in view of Mariassy (Experimental Lung Research, 1983, 4(4): 293-314), as evidenced by Kenney (Diagnostic Pathology, 2007, 2:21).
Kassab teaches a method for harvesting and fixing mammalian visceral pleura for use in medical applications (p 14, Detailed Description, para 2 – p 15, para 1).
Regarding claim 1: Kassab teaches harvesting the visceral pleura from a mammal, then fixing the dissected tissue in a fixative (p 22, para 1).
Kassab does not teach a method of processing a tissue, wherein the tissue is mediastinal pleura from the parietal pleura.
Kassab teaches that it is advantageous to identify and process thin scaffold biological tissue that consists of largely elastin and some collagen fibers, since elastin is not as prone to fixation as collagen, and thus fixation of tissue with elastin largely maintains its elasticity and biological mechanical activity (p 15, para 2).
Mariassy teaches that the mediastinal parietal pleura comprises a fibroelastic meshwork with massive three-dimensional network of elastic fibers (p 299, Table 1, Row 5).
Therefore, it would have been prima facie obvious for a person of ordinary skill in the art before the effective filing date of the claimed invention to have modified the method of Kassab by using mediastinal parietal pleural tissue. One of ordinary skill in the art would have been motivated to make this modification because Kassab teaches that an ideal tissue for use in medical applications comprises elastin (p 15, para 2), and Mariassy teaches that the mediastinal pleura comprises a fibroelastic meshwork with massive three-dimensional network of elastic fibers (p 299, Table 1, Row 5). One of ordinary skill in the art would have had a reasonable expectation of making this modification because Mariassy teaches that mediastinal parietal tissue can be processed and fixed.
Furthermore, Kassab teaches that the visceral pleura becomes continuous with the parietal pleura that covers the diaphragm, chest wall and mediastinum (p 15, para 3). Given the teachings of Kassab, there was a reasonable expectation that visceral pleura and mediastinal parietal pleura would work equivalently as a fixed tissue sample. Therefore, it would have been prima facie obvious for someone of ordinary skill in the art before the effective filing date of the claimed invention to have substituted visceral pleura tissue with mediastinal parietal pleura tissue with predictable results. Substitution of one element for another known in the field, wherein the result of the substitution would have been predictable, is considered to be obvious. See KSR International Co. v Teleflex Inc 82 USPQ2d 1385 (US 2007) at page 1395.
With respect to the order of steps in claim 1, it is noted that the courts have held that any order of performing process steps is prima facie obvious in the absence of new or unexpected results (In re Gibson, 39 F.2d 975, 5 USPQ 230 (CCPA 1930); Ex parte Rubin, 128 USPQ 440 (Bd. App. 1959)). See MPEP §2144.04 (IV)(C). Therefore, the claimed order of steps is an obvious variant of the steps of the cited prior art.
The combination of prior art cited above in all rejections under 35 U.S.C. 103 satisfies the factual inquiries as set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966). Once this has been accomplished the holdings in KSR can be applied (KSR International Co. v. Teleflex Inc. (KSR), 550 U.S. ___, 82 USPQ2d 1385 (2007): "Exemplary rationales that may support a conclusion of obviousness include: (A) Combining prior art elements according to known methods to yield predictable results; (B) Simple substitution of one known element for another to obtain predictable results; (C) Use of known technique to improve similar devices (methods, or products) in the same way; (D) Applying a known technique to a known device (method, or product) ready for improvement to yield predictable results; (E) "Obvious to try" - choosing from a finite number of identified, predictable solutions, with a reasonable expectation of success; (F) Known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art; (G) Some teaching, suggestion, or motivation in the prior art that would have led one of ordinary skill to modify the prior art reference or to combine prior art reference teachings to arrive at the claimed invention. In the present situation, rationales B and G are applicable, as set forth in the rejections above. The cited prior art meets the criteria set forth in both Graham and KSR. Therefore, Kassab, in view of Mariassy, renders obvious claim 1.
Regarding claims 2-3: Kassab teaches acquiring tissue from a deceased mammal, including a pig, horse, cow, goat, sheep, and human (p 1, para 5; p 24, para 2).
Regarding claim 6: Kassab teaches cleaning the desired tissue by removing fat and muscle covering the tissue (p 22, para 1).
Regarding claim 7: Kassab teaches positioning the tissue sample upon a mount having known dimensions (p 22, para 1).
Regarding claim 8: Kassab teaches configuring the processed tissue into medical articles, wherein the products include stent covers and tendon replacements, among others (p 24, para 5 – p 26, para 6).
Regarding claim 9: Kassab teaches that the product comprises a first surface and a second surface (e.g., Fig. 5A-D). Kenney shows that the parietal pleura comprises elastin fibers and are lined with mesothelial cells (Abstract).
Regarding claim 10: Kassab teaches a product comprising a frame configured to retain a mammalian tissue, such that when the product is positioned within a mammalian lumen, fluid native to the mammalian lumen passes through a lumen defined within the product (p 10, para 2).
Regarding claims 11-12: Kassab teaches a product comprising a valve, which has a bileaflet or trileaflet configuration (p 25, para b).
Regarding claim 13: Kassab teaches an embodiment of the invention, wherein the fixed sample comprises tissue having stretchability and durability properties to allow the fixed sample to move relative to the fluid flow through the lumen defined within the tissue product (p 6, para 2).
Regarding claim 14: Kassab teaches an embodiment of the tissue processing method, wherein the method comprises the step of decellularizing at least a portion of the sample of pulmonary region tissue prior to performing the fixing step (p 8, para 3).
Response to Arguments
Re: Rejections under 35 U.S.C. § 102 over Mariassy
Applicant argues: The order-of-steps amendment to claim 1 distinguishes Mariassy. Mariassy fixes the parietal pleura first, then takes samples from the mediastinal regions for microscopy (p. 294). The claimed method requires acquire -> select the mediastinal sample -> fix the selected sample. This order allows inspection and selection of only undamaged tissue before fixation - a critical distinction for producing implantable medical articles that Mariassy does not teach or suggest.
In response: Applicant’s arguments have been fully considered, but are not persuasive. As set forth above, the rejection of claims 1-3 under 35 USC 102 over Mariassy has been withdrawn in light of the amendment to claim 1. However, as set forth in the body of the rejection of claims 1-3 under 35 USC 103, Mariassy nevertheless renders obvious claim 1.
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., inspection and selection of only undamaged tissue for producing implantable medical articles) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Re: Rejections under 35 U.S.C. § 103 over Kassab, in view of Mariassy
Applicant argues: It would not have been obvious to a POSITA at the effective filing date to modify Kassab's method (which teaches harvesting and fixing pulmonary ligament or visceral pleura) to instead use mediastinal pleura tissue from the parietal pleura for the following reasons:
1. Different Anatomical Source and Harvesting Technique. Kassab teaches selecting pulmonary ligament or visceral pleura. The present invention specifically claims selecting mediastinal pleura from the parietal pleura - the portion lining the mediastinum and separating the right and left lungs. The specification at pages 5-6 and Figure 6F-G provides detailed, unique harvesting instructions. The examiner recognized this distinction in the restriction requirement. There is no teaching or suggestion in Kassab to target this specific anatomical region.
In response: Applicant’s arguments have been fully considered, but are not persuasive. In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., detailed, unique harvesting instructions at pages 5-6 and Figure 6F-G of the specification) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Furthermore, as set forth in the restriction requirement mailed 07/10/2025, the basis of the restriction requirement was not based on the use of mediastinal pleura in claim 1; indeed, the invention of Group III (drawn to cancelled claims 19-20) also required the use of mediastinal pleura. As recited in the restriction requirement, “the inventions as claimed are directed to distinct processes using mediastinal pleura tissue. The process of invention I [claims 1-15] is related to tissue fixation, whereas the process of invention III [claims 19-20] is related to making a tissue product comprising a frame etc., and there is no tissue fixation involved” (p. 2-3).
Finally, as set forth in the body of the rejection, Kassab, in combination with Mariassy, teaches the use of mediastinal parietal pleura tissue. In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
Applicant argues: 2. Unexpected Structural and Mechanical Properties. Mediastinal pleura is mechanically isotropic (random collagen fiber orientation, 3D elastic meshwork per Mariassy p. 299), unlike the anisotropic pulmonary ligament. This isotropy provides uniform stretch in all directions - highly advantageous for valve leaflets and other dynamic applications. A POSITA would not have expected this superior performance from switching tissue sources.
In response: Applicant’s arguments have been fully considered, but are not persuasive. In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., that the use of mediastinal pleura is highly advantageous for valve leaflets and other dynamic applications) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Applicant argues: 3. Dual-Sided Mesothelial Lining - A Critical and Unappreciated Advantage. Mediastinal pleura has mesothelial cells on both surfaces, providing slippery, non-adhesive, protective, and antithrombotic properties on both sides (spec p. 17-18, [0036]-[0037]; Figure 1). Visceral pleura has mesothelium on only one side. This dual-sided architecture is a significant, unrecognized advantage for luminal implants. The examiner's own enablement rejection acknowledges this feature yet fails to recognize its non-obvious implications.
In response: Applicant’s arguments have been fully considered, but are not persuasive. The rejection of claim 15 (now cancelled) under 35 USC 112(a) was not directed to the use of mediastinal pleura tissue in the method recited therein. Rather, claim 15 was rejected under 35 U.S.C. 112(a) because the specification, while being enabling for using the fixed sample of mammalian mediastinal pleural tissue in a surgical procedure to treat a patient of a compatible mammalian species, wherein the tissue has been formed into a product as recited in claim 8, does not reasonably provide enablement for treating a patient of any species using any mode of treatment, using the fixed sample of mediastinal pleural tissue.
Applicant argues: 4. Larger Surface Area and Optimal Thickness. Mediastinal pleura provides larger harvestable surface area and an ideal processed thickness (~50-80 μm) for thin, flexible medical articles (spec p. 19-20, [0045], [0052]). Kassab's ligament averaged 102 μm. A POSITA would not have been motivated to switch to a thicker, anisotropic tissue when this superior source was available.
In response: Applicant’s arguments have been fully considered, but are not persuasive. As set forth in the body of the rejection above, Kassab does not teach the use of mediastinal pleura; Kassab teaches that it is advantageous to identify and process thin scaffold biological tissue that consists of largely elastin and some collagen fibers, (p 15, para 2), and Mariassy teaches that the mediastinal parietal pleura comprises a fibroelastic meshwork with massive three-dimensional network of elastic fibers (p 299, Table 1, Row 5). As set forth in the body of the rejection, the use of thicker tissue is not the motivation for modifying the method of Kassab with the teachings of Mariassy.
Applicant argues: 5. No Motivation to Combine; High Unpredictability in the Art. The examiner's enablement rejection candidly admits "a high level of unpredictability" in this field, that xenotransplantation prior art was "largely limited to porcine tissue in primate patients," and that "the prior art does not teach combinations and permutations of xenotransplantation within, or beyond, mammalian species." Under KSR, "obvious to try" requires predictable solutions. The examiner's own analysis establishes the opposite. A POSITA would not have had a reasonable expectation of success in using this previously unappreciated tissue source for medical articles of manufacture.
In response: Applicant’s arguments have been fully considered, but are not persuasive. As set forth in the response to argument (3), the rejection of claim 15 under 35 U.S.C. 112(a) was regarding the scope of the method in claim 15: namely, that a method of treating a patient of any species using any mode of treatment (i.e., cross-species treatment and the treatment of any disease, via any mode of administration) using the fixed sample of mediastinal pleural tissue is not enabled by the instant specification.
With respect to the rejection of claim 1 under 35 USC 103 over Kassab, in view of Mariassy: as set forth in the body of the rejection, given the teachings of Kassab, there was a reasonable expectation that visceral pleura and mediastinal parietal pleura would work equivalently as a fixed tissue sample. Furthermore, it is noted that the rejection of claim 1 under 35 USC 103 over Kassab, in view of Mariassy, relies on (1) Simple substitution of one known element for another to obtain predictable results and (2) Some teaching, suggestion, or motivation in the prior art that would have led one of ordinary skill to modify the prior art reference or to combine prior art reference teachings to arrive at the claimed invention. It does not rely on the "Obvious to try" rationale (i.e., choosing from a finite number of identified, predictable solutions, with a reasonable expectation of success), as asserted by Applicant.
Applicant argues: 6. Unexpected Results. The use of mediastinal pleura enables superior medical articles (excellent valve coaptation, no blood stagnation, tissue-tissue contact with vessel wall, pre-stretch preservation before fixation - see spec [0112]). These advantages were not recognized or suggested in Kassab or Mariassy.
In response: Applicant’s arguments have been fully considered, but are not persuasive. In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., that the use of mediastinal pleura enables superior medical articles) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Conclusion
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Risa Takenaka whose telephone number is (571)272-0149. The examiner can normally be reached M-F, 12-7 EST.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Peter Paras can be reached at (571) 272-4517. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/RISA TAKENAKA/ Examiner, Art Unit 1632
/KARA D JOHNSON/ Primary Examiner, Art Unit 1632
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