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 .
Status of Claims
Claims 1-8, 11-20 are pending. Claim 5 remains withdrawn from consideration. References not included with this Office action can be found in a prior action. Any rejections of record not particularly addressed below are withdrawn in light of the claim amendments and applicant’s comments.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims are 1-4, 6-8, 11-20 rejected 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.
Claim 1 has been amended to recited “wherein said cardiac construct is suspended within the fibrin hydrogel and a structural support material is not within the fibrin hydrogel.” However lines 1-3 recite making an intermediate cardiac construct by depositing a mixture of cardiac cells, fibrinogen, gelatin, and water on a support and then producing the final construct by crosslinking the intermediate construct with thrombin as denoted by the recitation “and produce a cardiac construct comprised of live mammalian cardiac cells that together spontaneously beat in a fibrin hydrogel.” Thus it is unclear how the produced cardiac construct is suspended within the fibrin hydrogel when the cardiac construct is made of the cells and fibrin hydrogel. The claims will be interpreted consistent with the specification that the cells are suspended in the fibrin hydrogel.
Further the claim recite “wherein the cardiac construct comprises cardiomyocytes”. It is unclear if applicant is intended to limit the cardiac cells in line 2 or referring to a different construct since “the cardiac construct” (the produced final construct) in line 5 does not comprise cardiomyocytes. Thus, “the cardiac construct” in line 8 comprising cardiomyocytes lacks antecedent basis and it is unclear if applicant is referring to another construct. Applicant is advised to also amend the dependent claims to use consistent terminology, i.e. cardiac cells or cardiomyocytes.
Lastly, the claim recites “a support” in line 3 of the claim and “a structural support” in line 7 of the claim. It is unclear if applicant is referring to the support in line 3 when reciting the support material is not within the fibrin hydrogel. Further, the fibrin hydrogel in itself function (and other polymers including collagen/ECM/elastin) as a support material for the cardiac cells. It is unclear if applicant is attempting to exclude all other polymers from the hydrogel. Thus, the recitation a structural support is not within the fibrin hydrogel is unclear.
The following is a quotation of 35 U.S.C. 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
The following is a quotation of pre-AIA 35 U.S.C. 112, fourth paragraph:
Subject to the following paragraph [i.e., the fifth paragraph of pre-AIA 35 U.S.C. 112], a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claims 6, 11-14 are rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends.
Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
Claim 1 recites the cardiac construct comprises cardiomyocytes, construed to be limiting the live mammalian cardiac cells in lines 2. Claim 6 recites the live mammalian cardiac cells are cardiomyocytes which does not further limit the base claim.
Claim 1 recites the construct does not comprise a structural supporting material; however, the depending claims recite polymers that are further included in the hydrogel. As evidenced by the art cited below (Camci-Unal et al) the polymers claimed in dependent claims provide support to the construct and can read on broadest reasonable interpretation of “a structural supporting material.” Thus, the claims do not further limit the base claim and broaden the scope.
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-4, 6-8, 11-20 are rejected 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. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention. This is a new matter rejection.
Claim 1 has been amended to recited “wherein said cardiac construct is suspended within the fibrin hydrogel and a structural support material is not within the fibrin hydrogel.” The 112(b) and (d) should be noted in which the hydrogel itself functions as a support material along with the materials claimed in the dependent claims. Second, the specification does not contemplate or describe a general discussion of support materials and its placement in or outside the fibrin hydrogel. Page 11 of the specification is noted in which specific supporting polymers are taught that can be placed adjacent to the hydrogel or alternating with the hydrogel and supporting polymer which may provide some support for excluding certain supporting polymers in the hydrogel. However, within the fibrin hydrogel is not discussed and the genus of structural supporting material which can encompass supports taught in the art that applicant is attempting to carve around (silicone supports, cantilvers, etc). Also, note the instant specification does not describe a cardiac construct comprising cardiac cells and fibrin hydrogel that is suspended in another fibrin hydrogel which is how the wherein clause of line 6 may be interpreted.
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.
Claims 1-2, 4, 6-8, 11-19 are rejected under 35 U.S.C. 103 as being unpatentable over Forgacs et al (U.S. PGPUB 20100041134) in view of Camci-Unal et al (2014, NPG Asia Materials (2014) 6, e99: 1-12; reference U).
Regarding claim 1, Forgacs teaches methods for tissue engineering multicellular bodies comprising a plurality of living cells, said method comprising:
depositing a mixture comprising live mammalian cells, fibrinogen, gelatin, and water on a support (reads on to form an intermediate construct);
and contacting thrombin to said mixture comprising multicellular bodies in an amount effective to cross-link said fibrinogen and produce engineered tissue construct (see abstract, paragraphs 11, 14, 62, 74 & 91-92, and Example 3).
Regarding claims 1-2 and 6-7, Forgacs teaches embodiments wherein the multicellular bodies are spheroids (both multicellular bodies and spheroid read on “organoid”) are bioprinted three-dimensional constructs, and wherein the cells are contractile cells, and specifically cardiomyocytes (see paragraphs 6, 58, 78, 84, 88, 92 & 120 and Example 2). Forgacs teaches the cells are suspended without said cells being anchored to a support material (see abstract, paragraphs 11, 14, 62, 74 & 91-92, and Example 3). The cells are incubated for a time period in a culture medium to foster coherence and maturity [96]. The medium is taught to contain growth factors compatible to the tissue and this is known to those skill in the art. [63]
Regarding claims 9 and 11-16, Forgacs teaches the mixture can further comprise other support materials including hyaluronic acid (reads “glycosaminoglycans), elastin, collagen, growth factors, and extracellular matrix components (ECM) that support cohesion of the cells (see paragraphs 62-63, 74, 91, 97 & 131-132 and Example 2).
Regarding claim 18, Forgacs teaches the hydrogel has a gel like viscosity (viscoelastic consistency) and manipulation thereof.
Regarding claim 19, Forgacs teaches a number of methods may be used to deposit the mixture, including depositing using extrusion from a pipette, nozzle, or needle, or extruded from the capillary tubes with the plunger (see paragraphs 119 & 135); reads on “extruding the mixture through a syringe”.
Forgacs teaches the same method of depositing a mixture of live cells (that may be cardiomyocytes with fibrinogen, gelatin and crosslinking with thrombin to make a fibrin hydrogel comprising the live cells). Forgacs suggest placing the hydrogel in a cell culture medium to facilitate cell maturity and cohesion and form a three dimensional organoid. Summarily Forgacs teaches all the method steps to produce the construct and placing it is a media to reach maturity and cohesion. Thus, following Forgacs methodology, the fibrin hydrogel comprising the cardiomyocytes places in the culture medium would necessarily spontaneously beat together as they mature and have the same functional characteristics claimed.
However, Camci Unal is also cited to support said position that the components of Forgacs would lead to the same functional limitations claimed.
Camci-Unal teaches that fibrin hydrogels comprising cardiomyocytes allow for contraction of the cells, and enable the cell to deposit their own ECM and remodel for form fibers resulting in beating behavior. Camci-Unal also teaches the use of ECM (decellularized) also provides structural support to maintain cardiomyocytes viability and promote vascularization. It was shown constructs maintained in culture maintained synchronous beating behavior for 2 months. cell viability and function, that the addition of ECM to hydrogels supported high cardiomyocyte viability and function, and that cardiomyocytes in a hydrogel display spontaneous contractions for up to 8 weeks in the absence of an anchored support (see, col. 2 on page 1, col. 1 on page 2, col. 2 on page 6); having a viability of greater than 95% after 28 days of culture). Further, Camci-Unal teaches ECM promoted the function of contractile activities of the cardiac cells and this was seen when added to fibrin gels. Page 6. Further, Camci-Unal teach the aim of forming constructs is to have the construct closely mimic heart muscle and thus use of growth factors to increase cardiac differentiation and vascularization is taught and after culturing the construct cardiac markers include actinin, troponin. Page 6. Camci-Unal teaches incorporation of growth factors to increase cell survival and attachment. VEGF is taught to be added to the construct to prevent cellular damage. See page 7. Camci-Unal teaches hydrogels must be engineered to be tough and stretchable in order to provide tolerate the loading force and deformation of contractions. Page 3.
First as discussed above, it would have been obvious to one of ordinary skill in the art to look to the teachings of Forgacs and use the suggested cardiomyocytes as the live cells to form the construct (Forgacs refers as multicellular bodies). Following the teachings of Forgacs of depositing a mixture of live cells with fibrinogen, gelatin and crosslinking with thrombin to make a fibrin hydrogel comprising the live cells, and then placing the construct in a cell culture medium to facilitate cell maturity and cohesion and form a three dimensional organoid would lead to the claimed functional limitations of spontaneous beating. Further, as taught by Forgacs, placing the construct in a culture media to reach maturity and cohesion would lead to the claimed functional limitations of viability greater than 95% at day 28 and spontaneous beating. Forgacs teaches the same method steps claimed and are not distinguishable from the claimed invention. Further, the culturing of the construct as taught by Forgacs leads to the desired organoid. Thus, growing the organoid in the culture media until it has the desired characteristics as taught by Forgacs (maturity of the cell and cohesion) would be obvious.
Second, it would have been obvious to one of ordinary skill in the art to combine the teachings of Forgacs and Camci-Unal and expect Forgacs to have the same functional since Camci-Unal teaches fibrin hydrogels provide an environment that enables cardiomyocytes to deposit their own ECM and form aligned fibers to allow for synchronous beating in culture for 2 months. Further, it would have been obvious to look to Camci-Unal who teaches the addition of the same components taught by Forgacs including ECM, growth factors in the hydrogel to enhance the construct’s viability, growth, and vascularization. Camci-Unal teaches that fibrin hydrogel enables contractile activity and allow the cell to synchronously beat and ECM in fibrin hydrogels also enhances contractile activity.
Lastly it would be obvious to manipulate the viscosity of the hydrogel to provide mimic cardiac tissues and tolerate the loading force of contractile activity. Thus, the viscosity of the fibrin hydrogel would be within the ranges claimed and the manipulation of the viscosity to provide the necessary rigidity and stiffness required following the teachings of Forgacs and Camci-Unal would be obvious.
Therefore, the invention as a whole would have been prima facie obvious to a person of ordinary skill at the time the invention was made.
Claims 3 and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Forgacs et al (U.S. PGPUB 20100041134) in view of Camci-Unal et al (2014, NPG Asia Materials (2014) 6, e99: 1-12; reference U) and further in view Chen et al (U.S. PGPUB 2014/0220555).
The teachings of Forgacs and Camci-Unal are discussed and relied upon above.
Forgacs does not teach contacting with administering isoproterenol.
Chen teaches that the microtissues are three-dimensional micro-scale constructs of cardiac cells embedded within collagen/fibrin 3D polymerized matrices, wherein the cardiac cells may be cardiomyocytes (see paragraphs 10-11, 43, 71 & 91). Chen teaches introduction of isoproterenol can produce reproducible, dose-dependent effects on microtissue contractility and beating frequency, and that treatment with quinidine can be utilized for dose-response including a contractility response to the dose (see paragraphs 95, 109 & 139). Chen also teaches the use of isoproterenol to assess cardiac maturation. Chen further teaches that it is useful for ECM can be adapted to replicate in vivo environmental characteristic, and a range of ECM stiffness from 0.5 to 12 kPa is similar to the ranges observed during cardiac tissue development (see paragraphs 78 & 110).
It would have been obvious to combine Forgacs and Camci-Unal with Chen and administer isoproterenol. One would have been motivated to do so since Chen teaches isoproterenol can produce dose dependent beating and contractility. [It should be noted since applicant argues that Chen teaches a different method, the method of making the fibrin hydrogel does not change the ability of isoproterenol to increase beating] Thus, if one desired to increase beating and contractility, one would have further added isoproterenol. Further, Chen teaches isoproterenol can be used to assess the cardiomyocytes maturity and one would have been motivated to add isoproterenol to assess cardiac maturity since Forgacs teaches maintaining the organoid until maturity is reached. Lastly, Chen teaches the use of ECM with the claimed range which is similar to cardiac tissue provides the necessary rigidity for contractions.
Claim 20 is rejected under 35 U.S.C. 103 as being unpatentable over Forgacs et al (U.S. PGPUB 20100041134) in view of Camci-Unal et al (2014, NPG Asia Materials (2014) 6, e99: 1-12; reference U) and further in view of Zhang et al (U.S. PGPUB 2005/0118144).
The teachings of Forgacs and Camci-Unal are discussed and relied upon above.
Forgacs does not teach contacting with aprotinin.
Regarding claim 20, Zhang is drawn to methods and materials related to fibrin-based biomatrices, and Zhang teaches said biomatrices are made by combining fibrinogen and a thrombin, and that flexibility can be altered by adding a solution comprising the fibrinolytic inhibitor aprotinin (see paragraphs 2 & 28). Zhang teaches fibrin matrix provides structural and mechanical support for the cells, including cardiomyocytes, and that said cells in said matrix maintain cellular, mechanical, and electromechanical characteristics comparable to native tissue (see paragraph 70).
It would have been obvious to further combine Forgacs and Camci-Unal with Zhang to utilize aprotinin with Forgacs’ fibrin containing gel matrix. A person of ordinary skill in the art would have had a reasonable expectation of success in utilizing aprotinin with Forgacs’ fibrin containing gel matrix because Zhang establishes that flexibility can be altered by adding a solution comprising the fibrinolytic inhibitor aprotinin. The skilled artisan would have been motivated to utilize aprotinin with Forgacs’ fibrin containing gel matrix because Zhang establishes that such gels are made using thrombin, and that flexibility can be altered by adding a solution comprising the fibrinolytic inhibitor aprotinin, therefore these components are specifically taught to be useful.
Therefore, the invention as a whole would have been prima facie obvious to a person of ordinary skill at the time the invention was made.
Response to Arguments
Applicant's arguments filed 12/22/2025 have been fully considered but they are not persuasive. The amendments have necessitated new grounds of rejections but the pertinent arguments to the references will be addressed.
It should be noted that as discussed in the rejection above, Forgacs is suggestive of the method of making the cardiac construct as claimed and thus would necessarily have the same functional limitation.
Applicant argues Camci-Unal and Chen teach different methods and thus they cannot support any deficiencies in Forgacs. However, these arguments are not persuasive since Forgacs teaches the method of making and Camci-Unal is only relied upon to show Forgacs components would necessarily lead to the same function. Camci-Unal, as discussed in the rejection, teaches components used in the construct allow for the construct to function, i.e fibrin hydrogels allow for contractions not the method of making the fibrin hydrogel and ECM enhances contraction. Applicant argues that Camci-Unal refers to the methods of Schaaf and Schaaf teaches the silicone posts cause sarcomeric organization. However, this is incorrect since the discussion of fibrin hydrogels does not cite Schaaf and rather two different references (references 32 and 39). Moreover, this argument that the silicone posts leads to the beating is a mischaracterization of Camci-Unal that clearly states “Degradation of the fibrin gel enabled the encapsulated cardiomyocytes to deposit their own ECM, remodel, and form aligned fibers. The results indicated that the alignment of the cells augmented the twitch force” Camci-Unal further teaches “ECM hydrogels supported high cardiomyocyte viability.” It is further noted that the NPL teaches ECM promoted the function of contractile activities of the cardiac cells and this was seen when added to fibrin gels. Schaaf is not a reference cites in this paragraph. Regarding applicant’s argument of the viability, again Forgacs teaches the same hydrogel components, the same method steps, and placing the construct in a culture to reach maturity. Thus, Forgacs teaches the invention as claimed. The specification has been reviewed to see if the functional limitation is caused by any other step and it does not appear so.
Applicant argues the merits of Chen and Chen uses cantilevers to impact the contraction. However, as discussed above Chen is not relied upon for the method of making.
Conclusion
All claims are rejected.
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/SHARMILA G LANDAU/Supervisory Patent Examiner, Art Unit 1653
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