DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application is being examined under the pre-AIA first to invent provisions.
Claims 1-3, 7-10, 12 and 13 are pending in this application and were examined on their merits.
The rejection of Claims 1-3, 7-10, 12 and 13 under 35 U.S.C. § 112(a) or 35 U.S.C. §112 (pre-AIA ), first paragraph, as failing to comply with the written description
Requirement has been withdrawn in view of the Applicant’s amendment to Claim 1 filed 12/06/2025 removing the New Matter.
The rejection of Claims 1-3, 7-10, 12 and 13 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inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention, has been withdrawn in view of the Applicant’s amendment to Claim 1 filed 12/06/2025 removing the New Matter.
Claim Rejections - 35 USC § 103
The following is a quotation of pre-AIA 35 U.S.C. 103(a) which forms the basis for all obviousness rejections set forth in this Office action:
(a) A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1-3, 7-10, 12 and 13 are rejected under pre-AIA 35 U.S.C. § 103(a) as
being unpatentable over Van Winkle et al. (1995), cited in the IDS, in view of Chang et
al. (2007) and Brune et al. (2007), as evidenced by Schmuck et al. (2014), all of record.
Van Winkle et al. teaches isolating cardiac fibroblasts from cardiac tissue,
passaging the cells at least once, plating and culturing the expanded cardiac fibroblasts,
wherein the cells secrete a cardiac ECM (cardiogel) that is attached to the surface on
which the expanded cardiac fibroblasts are plated, cultured and then contacting the
ECM with EDTA to decellularize the matrix, wherein the ECM remaining on the plates is
scraped from the plates and analyzed (Pg. 479, Column 1, Lines 35-55), reading on
Claim 1.
With regard to the limitations of Claims 7-8, "comprising seeding the extracellular
matrix with one or more cells that are therapeutic for cardiac disease or injury" and
"wherein the one or more cells that are therapeutic for cardiac disease or injury are
bone marrow MSC", Chang et al. teaches seeding the decellularized 3D cardiac
extracellular matrix with bone marrow derived mesenchymal stem cells (MSC) (Pg. 371,
Column 1, Lines 20-27 and Pg. 378, Fig. 3).
With regard to the limitations of Claim 10, that the "decellularized 3D cardiac
extracellular matrix is essentially devoid of intact cardiac fibroblast cells", this is a
characteristic feature of the claimed, prepared 3-D cardiac ECM. As discussed above,
Van Winkle et al. teaches a method of preparing a cardiac fibroblast derived ECM,
comprising contacting the 3D cardiac extracellular matrix with a decellularizing agent
(EDTA) to produce a decellularized 3D cardiac extracellular matrix (Pg. 479, Column 1,
Lines 35-55). Therefore, the decellularized cardiac ECM of Van Winkle et al. would be
free of intact cardiac fibroblast cells.
With regard to the limitation of Claim 13, that "the cardiac ECM becomes
detached from the surface, forming a free-floating bioscaffold, the Van Winkle et al.
reference teaches that after treatment with EDTA the ECM is scraped free/detached
from the plates (thereby becoming free-floating).
The teachings of Van Winkle et al. were discussed above.
Van Winkle et al. does not teach a method wherein the expanded cardiac
fibroblasts into a culture having a cell density of 100,000 to 500,000 cells per cm2,
wherein the cardiac fibroblasts secrete a 3-dimensional cardiac extracellular matrix
having a thickness of 20-500, 30-200 or 15-150 µm that is attached to the surface on which the cardiac fibroblasts are plated, as required by Claim 1; step c) and Claims 2-3;
or wherein the contacting of the secreted cardiac ECM with the decellularizing
agent EDTA causes the cardiac ECM to become detached from the surface, forming a
decellularized, free-floating bioscaffold, as required by Claim 1, step d) and Claim 13;
wherein the decellularized ECM comprises one or more matricellular structural proteins, comprising fibronectin, collagen I, collagen III and elastin, wherein from 60- 90% of the structural proteins in the 3D cardiac ECM are fibronectin, as required by Claim 1, step d);
or wherein the matricellular protein is galectin-1, as required by Claims 9 and 12.
Chang et al. teaches a method of preparing a cardiac fibroblast derived 3D
matrix, comprising the steps of:
plating cardiac fibroblasts into a culture of 4 x 10⁵ cells in a 60 mm culture dish (4 x 10⁵ cells per 60 mm dish having a surface area of 28.27 cm² or 1 x 10⁵ cells/28.27
cm² = about 35,000 cells/cm²) or 1 x 10⁶ cells/well in 4 well culture dishes having a
surface area of 1.96 cm² (1.0 x 106/1.96 cm² = about 510,000 cells/cm²), thus establishing a de facto seeding density range below and slightly above (i.e.,
encompassing) the claimed seeding range;
and expanding/culturing the cells for 10 days, wherein the cells secrete a 3D
cardiac extracellular matrix (Pg. 371, Column 1, Lines 34-35 and Column 2, Lines 8-16
and Fig. 1);
contacting the 3D cardiac extracellular matrix with a decellularizing agent
(alkylaryl polyether alcohol and ammonium hydroxide) to produce a decellularized 3D
cardiac extracellular matrix (Pg. 371, Column 2, Lines 17-24 and Fig. 1);
and seeding the 3D cardiac extracellular matrix with bone marrow derived
mesenchymal stem cells (MSC) (Pg. 371, Column 1, Lines 20-27 and Pg. 373, Fig. 3),
wherein the MSC are isolated from bone tissue and expanded in culture for 1
passage (Pg. 371, Column 1, Lines 20-21 and Column 2, Lines 1-5).
Brune et al. teaches the optimization of culture parameters by plating ligament
fibroblasts at densities ranging from 5 x 10⁴ to 1 X 10⁸ cells/cm² (encompassing the
claimed range) for 3 days, 1, 2 or 3 weeks (Pg. 80, Column 1, Lines 1-2 and 16-31) with
the determination of an optimal plating density of 2 X 10⁵ cells/cm² cultured at 1-3 weeks (Pg. 82, Column 1, Lines 11- 14). The reference notes that ECM seeded with cells at a high seeding density of up to 1 X 10⁶ cells/cm² totally covered (e.g. 100% confluence) the seeded surface by 1-3 days and formed a continuous cellular layer on the (ECM) scaffold and produced new endogenous ECM while samples seeded with lower densities (5 x 10⁴ cells/cm²) took a week to reach the same stage of colonization (Pg. 81, Column 2, Lines 18-26).
It would have been obvious to those of ordinary skill in the art before effective
filing date of the instant invention to modify the method of Van Winkle et al. of preparing
a cardiac ECM comprising plating and culturing isolated, expanded cardiac fibroblasts
to plate the cardiac fibroblasts in the claimed density range, as taught by Chang et al. and Brune et al. because Chang et al. teaches plating cardiac fibroblasts into a culture in a de facto seeding density range below and slightly above (i.e., encompassing) the claimed seeding range; while Brune et al. teaches the optimization of plating fibroblasts at a range of from 5 X 10⁴ to 1 X 10⁸ cells/cm² (which encompasses the claimed seeding range) and determining an optimal density of 2 X 10⁵ cells/cm² which is also contained within the claimed range. Thus, the claimed culture density range is rendered prima facie obvious. Those of ordinary skill in the art before the effective filing date of the claimed invention would have been motivated to make this modification because Brune et al. teaches that optimal plating density for culturing fibroblasts is 2 X 10⁵ cells/cm², and that plating the cells at higher densities reduces the time to reach full confluence as compared to cells plated at lower densities. Thus, the ordinary artisan would seek to determine the optimal plating density to achieve the best plating result, i.e. a continuous ECM. Further, Brune et al. teaches that fibroblast plating density is an optimizable, result effective variable. There would have been a reasonable expectation of success in making this modification because at least both Chang et al. and Brune et al. are generally drawn to the same field of endeavor, that is, the culture of fibroblasts.
With regard to Claim 1, step d) and Claims 2, 3, 9 and 12, Schmuck et al.
evidences a 3-D cardiac fibroblast ECM matrix having a thickness of 50-150 µm
attached to the plating surface wherein the thickness of the matrices was dependent
upon fibroblast seeding density wherein optimal seeding density was greater than 5.5 x
10⁴ cells/cm² and less than 2.2 x 10⁵ cells/cm² with an optimal culture time of 10-14
days (Pg. 5, Lines 35-44 and Fig. 2E), wherein the ECM matrices comprise the
bioactive molecule matricellular protein galectin-1 (Pg. 15, Fig. 2E), and that cardiac
fibroblasts secrete an ECM composed of 82% fibronectin, collagen type I, collagen type
III and elastin (Pg. 1, Abstract). As Chang et al. teaches culturing the same cardiac
fibroblast cells as claimed for 10 days (within the optimal culture time described by
Schmuck) and Brune et al. teaches culturing fibroblasts from 1-3 weeks (encompassing
the optimal culture time described by Schmuck) and determining an optimal density of 2
x 10⁵ cells/cm² (contained within the claimed range and within the optimal culture
seeding density described by Schmuck), the prior art teaches culturing the same cells
as claimed in the same seeding density for similar culture times. Therefore, the
resultant thickness of the secreted cardiac ECM would also be the same as that
claimed. While Schmuck et al. is not prior art antedating the effective filing date it has
been cited because of its' teachings of universal facts (characteristics of cultured
cardiac fibroblast ECM) consistent with the MPEP at 2124. Thus, as Chang et al.
teaches culturing cardiac fibroblasts to produce a cardiac ECM, this would inherently
produce a cardiac ECM with the claimed structural proteins.
Response to Arguments
Applicant’s arguments, see Remarks, Pgs. 5-6, Section III filed 12/06/2025, with respect to the above withdrawn rejections have been fully considered. The rejections have been withdrawn in view of the amendment to Claim 1.
Applicant's remaining arguments filed 12/06/2025 have been fully considered but they are not persuasive with regard to the rejection under 35 U.S.C. § 103 as set forth above.
The Applicant argues that Chang does not teach either the claimed upper or lower cell plating density (Remarks, Pg. 7, Lines 18-22).
This is not found to be persuasive for the following reasons, as acknowledged by
the Applicant, Chang definitively teaches the claimed lower cell density. The Examiner notes Pg. 8, Lines 8-9 of the Remarks filed 07/03/2025 which state:
“Accordingly, Applicant contends that Chang only teaches the lower bound cell density
but NOT the upper bound density as the Action has asserted.”
Even if arguendo, the Chang reference does not teach the upper cell plating density, this limitation is met by Brune whom teaches plating another type of fibroblast at densities encompassing the claimed range, as well as the determination of the optimal plating density.
Thus, it would have been obvious to those of ordinary skill in the art to modify
the method of Van Winkle et al. and Chang et al. of preparing a cardiac ECM comprising plating and culturing isolated, expanded cardiac fibroblasts to plate the
cardiac fibroblasts in the claimed density range, because Brune et al. teaches the
optimization of plating fibroblasts at a range of from 5 x 10⁴ to 1 x 10⁸ cells/cm² (which
encompasses the claimed seeding range) and determining an optimal density of 2 X 10⁵
cells/cm² which is also contained within the claimed range. Thus, the claimed culture
density range is rendered prima facie obvious. Those of ordinary skill in the art before
the effective filing date of the claimed invention would have been motivated to make this
modification because Brune et al. teaches that optimal plating density for culturing
fibroblasts is 2 X 10⁵ cells/cm², and that plating the cells at higher densities reduces the
time to reach full confluence as compared to cells plated at lower densities. Thus, the
ordinary artisan would seek to determine the optimal plating density to achieve the best
plating result, i.e. a continuous ECM. Further, Brune et al. teaches that fibroblast
plating density is an optimizable, result effective variable. There would have been a
reasonable expectation of success in making this modification because at least Van
Winkle et al., Chang et al. and Brune et al. are generally drawn to the same field of
endeavor, that is, the culture of fibroblasts.
The Applicant argues that the Examiner’s position that Brune teaches cell density is an optimizable and result-effective variable is allegedly based on an understanding in the art that there is a need to optimize the cell density according to Brune and what the cell density should be, which are only derived from the Applicant’s disclosure. Applicant notes that Brune does not teach adjusting cell densities for force cardiac fibroblasts to grow on top of each other and form multilayers as set forth in the prior Declaration (Remarks, Pg. 8, Lines 12-18).
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). In this instance, as discussed in the prior action and above, Brune et al. teaches the optimization of culture parameters by plating ligament fibroblasts at densities ranging from 5 x 10⁴ to 1 X 10⁸ cells/cm² (encompassing the claimed range) for 3 days, 1, 2 or 3 weeks (Pg. 80, Column 1, Lines 1-2 and 16-31) with the determination of an optimal plating density of 2 x 10⁵ cells/cm² cultured at 1-3 weeks (Pg. 82, Column 1, Lines 11- 14). To obviate the claimed invention the prior art does not need to recognize that cardiac fibroblast plating density need be optimized for the specific purpose of Applicant.
The Applicant notes a teaching in the Specification indicating that a cardiac fibroblast plating density of less than 1 x 105 cells/cm2 will fail to produce a 3D cardiac ECM. Applicant asserts that Brune does not recognize this property, as the reference teaches an optimal seeding density range encompassing cell densities below the 1 x 105 cells/cm2 density. Applicant notes that Chang similarly discloses a lower cell density range which would not produce the claimed cardiac ECM. Applicant asserts that Van Winkle does not teach or suggest plating cell density and teaches an ECM with a thickness beyond the claimed parameter. Applicant concludes that the ordinary artisan would not have arrived at the claimed invention with the teachings of the cited prior art (Remarks, Pg. 8, Lines 16-35 and Pg. 9, Lines 16-30).
This is not found to be persuasive for the following reasons, the fact that both prior art references disclose lower limits in ranges of cell plating density which will not produce the claimed ECM is not evidence that the cell plating density is not a result-effective variable subject to routine experimentation and optimization. As discussed above and in the prior action, Chang teaches a de facto seeding density range below and slightly above (i.e., encompassing) the claimed seeding range while Brune teaches the optimization of plating fibroblasts at a range of from 5 x 10⁴ to 1 x 10⁸ cells/cm² (which encompasses the claimed seeding range) and determining an optimal density of 2 x 10⁵ cells/cm² which is also contained within the claimed range. Thus, the claimed culture density range is rendered prima facie obvious.
As discussed above and in the prior action, Van Winkle was cited only for its teaching of isolating cardiac fibroblasts from cardiac tissue, passaging the cells at least once, plating and culturing the expanded cardiac fibroblasts, wherein the cells secrete a cardiac ECM (cardiogel). The rationale for a finding of obvious the claimed thickness of the secreted cardiac ECM was based on the evidentiary reference Schmuck and the fact that the prior art cultures the same cells in the same cell plating/seeding density for a similar time. Thus, the resultant thickness of the secreted cardiac ECM would also be the same as that claimed. The Examiner maintains that the ordinary artisan in possession of the cited prior art would have found obvious the claimed invention for reasons of record set forth above and in the prior action.
The Applicant argues that the Examiner has not provided any rationale as to why the ordinary artisan would select the cell plating density of Brune over that of Chang which is not within the claimed range or the optimal range of Brune. Applicant asserts that because the claimed invention utilizes cardiac fibroblasts it would be more reasonable for the ordinary artisan to select the plating density of Chang over that of Brune as Chang also utilizes cardiac fibroblasts while Brune uses different fibroblasts (Remarks, Pg. 9, Lines 1-8 and Lines 11-12).
This is not found to be persuasive for the following reasons, the Examiner set forth rationale for a finding of obviousness both above and in the prior action.
That is, It would have been obvious to those of ordinary skill in the art to modify the method of Van Winkle et al. of preparing a cardiac ECM comprising plating and culturing isolated, expanded cardiac fibroblasts to plate the cardiac fibroblasts in the claimed density range, as taught by Chang and Brune because Chang teaches plating cardiac fibroblasts into a culture in a de facto seeding density range below and slightly above (i.e., encompassing) the claimed seeding range; while Brune teaches the optimization of plating fibroblasts at a range of from 5 x 10⁴ to 1 X 10⁸ cells/cm² (which encompasses the claimed seeding range) and determining an optimal density of 2 x 10⁵ cells/cm² which is also contained within the claimed range. Thus, the claimed culture density range is rendered prima facie obvious. Those of ordinary skill in the art before the effective filing date of the claimed invention would have been motivated to make this modification because Brune teaches that optimal plating density for culturing fibroblasts is 2 x 10⁵ cells/cm², and that plating the cells at higher densities reduces the time to reach full confluence as compared to cells plated at lower densities. Thus, the ordinary artisan would seek to determine the optimal plating density to achieve the best plating result, i.e. a continuous ECM. Further, Brune teaches that fibroblast plating density is an optimizable, result effective variable thus providing a rationale for the use of the disclosed fibroblast plating densities even if used to plate and culture different fibroblasts.
The Applicant argues that the Examiners position that Chang discloses a cell density of 35,000-510,000 cells/cm2 without addressing the Applicant’s argument that Chang does not teach the upper limit value (Remarks, Pg. 9, Lines 9-11).
This is not found to be persuasive for the reasoning provided both above and in the prior action, that is, Even if arguendo, the Chang reference does not teach the upper cell plating density, this limitation is met by Brune whom teaches plating another type of fibroblast at densities encompassing the claimed range, as well as the determination of the optimal plating density. Thus, it would have been obvious to those of ordinary skill in the art to modify the method of Van Winkle et al. and Chang et al. of preparing a cardiac ECM comprising plating and culturing isolated, expanded cardiac fibroblasts to plate the cardiac fibroblasts in the claimed density range, because Brune et al. teaches the optimization of plating fibroblasts at a range of from 5 x 10⁴ to 1 x 10⁸ cells/cm² (which encompasses the claimed seeding range) and determining an optimal density of 2 X 10⁵ cells/cm² which is also contained within the claimed range. Thus, the claimed culture density range is rendered prima facie obvious.
Conclusion
No claims are allowed.
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 PAUL C MARTIN whose telephone number is (571)272-3348. The Examiner can normally be reached Monday-Friday 12pm-8pm 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, Sharmila G Landau can be reached at (571) 272-0614. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/PAUL C MARTIN/ Examiner, Art Unit 1653
/SHARMILA G LANDAU/Supervisory Patent Examiner, Art Unit 1653