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
Claim 6 is canceled. Claims 7-14 are new. Claims 1-5, and 7-14 are pending.
Priority
The instant claims are entitled to an effective filing date of 03/11/2021.
Specification
The amendment to the specification filed 03/16/2026 is objected to under 35 U.S.C. 132(a) because it introduces new matter into the disclosure. 35 U.S.C. 132(a) states that no amendment shall introduce new matter into the disclosure of the invention. The added material which is not supported by the original disclosure is as follows:
The term “about”, as used herein, refers to “±5%”. See p. 2, specifically the ‘amendments to the specification’ section.
Applicant is required to cancel the new matter in the reply to this Office Action.
Applicant is reminded of the proper language and format for an abstract of the disclosure.
The abstract should be in narrative form and generally limited to a single paragraph on a separate sheet within the range of 50 to 150 words in length. The abstract should describe the disclosure sufficiently to assist readers in deciding whether there is a need for consulting the full patent text for details.
The language should be clear and concise and should not repeat information given in the title. It should avoid using phrases which can be implied, such as, “The disclosure concerns,” “The disclosure defined by this invention,” “The disclosure describes,” etc. In addition, the form and legal phraseology often used in patent claims, such as “means” and “said,” should be avoided.
The instant abstract recites “A method for producing human collagen structures with controlled characteristics”, which repeats information given in the title “producing human collagen structures with controlled characteristics”.
Response to Arguments
Objections to the Specification: Applicant's arguments filed 03/16/2026 have been fully considered but they are not persuasive.
Applicant argues that the specification has been amended. See the remarks p. 10 fourth sentence.
This argument is not persuasive, because line 1 of the amended abstract still repeats information in the title. Furthermore, the corrected abstract filed 03/16/2026 was not presented on a separate sheet, apart from any other text as previously required. See the action mailed 10/16/2025 p. 3 paragraph 4 for this requirement.
Claim Objections
Claims 1-5, 8-9, and 11-13 are objected to because of the following informalities:
In claims 1-5, the markings indicate changes relative to the original claims rather than the previous claims in a preliminary amendment filed 06/16/2023. 37 CFR 1.121 indicates that all claims being currently amended in an amendment paper shall be submitted with markings to indicate the changes that have been made relative to the immediate prior version of the claims.
Claims 1-2, 8-9, and 11-13 recite “).”, which should be amended to “)” such that the additional periods are deleted because MPEP 608.01(m) states that periods may not be used elsewhere in the claims except for abbreviations.
Claim 1 recites “on which the one or more molds and the collagen-containing solution located therein” in part x), which should be replaced with “on which the one or more molds and the collagen-containing solution are located”.
Appropriate correction is required.
Claim Rejections - 35 USC § 112(a)
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 1-5, and 7-14 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. The amendment filed on 03/16/2026 has introduced new matter into the claims.
Claim 1, as filed on 03/16/2026, recites a method to produce human collagen structures with controlled characteristics, comprising the steps of:
a). collecting human collagen-containing tissue samples comprising particles having surface proteins and collagen fibers comprised of collagen molecules, wherein said samples exhibit a high degree of biocompatibility
b). removing unwanted tissues or fluids from the human collagen-containing tissue samples and drying the human collagen-containing tissue samples;
c). reducing the size of desired particles of collagen of 0.5 to 1 mm to create a uniform conditioned tissue sample;
d). combining the dried conditioned tissue sample with a sodium hydroxide solution, have a molar concentration of 0.5 – 2 M, using a ratio of 100 mL of sodium hydroxide solution per one gram of dried conditioned tissue;
e). mixing the conditioned tissue samples and sodium hydroxide solution using magnetic agitation for 2-6 hours or until surface proteins are removed and collagen fibers are exposed;
f). removing any excess sodium hydroxide from the conditioned tissue samples in sodium hydroxide solution;
g). washing the conditioned tissue samples with distilled water until the pH of the conditioned tissue samples value is about 7-8;
h). drying the washed conditioned tissue samples;
i). performing enzymatic hydrolysis using the following steps:
1). promoting a solubilization of the collagen fibers by mixing the dried conditioned tissue samples with 0.02-0.5 M acid using a solution of pepsin in acid, using a ratio of 200 g of the pepsin/acid solution for each kg of dried conditioned tissue samples used, wherein specific and controlled removal of terminal carboxy and amino groups of the conditioned tissue samples occurs;
2). removing any excess pepsin/acetic acid solution and drying the treated conditioned tissue samples;
3). adding an intermediate acid solution, comprising 200 mL of acetic acid per each g of dried conditioned tissue samples;
4). after 48 hours, adding 250 mL of acid per each g of dried conditioned tissue sample; to promote the
5). filtering the treated, conditioned tissue sample acidic acid solution to promote the removal of residues of non-collagenous tissue structures;
j). creating a salt concentration greater than 0.5 M by adding sodium chloride at a rate of 58.44 g of sodium chloride per one L of treated, conditioned tissue sample acid solution creating a treated, conditioned tissue sample in acid solution;
k). homogenizing the treated, conditioned tissue sample acid solution using magnetic stirring;
l). precipitating the collagen molecules by continually stirring the treated, conditioned tissue sample acid solution for 2-6 hours,
m). sieving the resulting solution to a particle size between about 125-850 μm;
n). recovering the collagen fibers from the sieve and drying the recovered collagen fibers;
o). solubilizing the dried recovered collagen fivers in an acetic acid solution having a ratio of 350 mL acetic acid per one g of dried conditioned tissue creating a collagen-containing solution;
p) purifying the collagen-containing solution with a dynamic dialysis system by employing the following steps:
1). pouring the collagen-containing solution into a porous membrane having a contact surface and a pore size of about 12-14 kD, wherein the porous membrane removes impurities from the collagen-containing solution when the collagen-containing solution is introduced into a dialysis buffer solution consisting of 0.02 – 0.5 M acetic acid, wherein salt molecules in the collagen-containing solution having a salt concentration of 1-2M and the dialysis buffer solution are exchanged due to a concentration differential between the dialysis buffer solution and the collagen-containing solution having a salt concentration of 1-2 M, wherein the dialysis buffer solution and the collagen-containing solution having a salt concentration of 1-2M and the dialysis buffer solution are exchanged due to a concentration differential between the dialysis buffer solution and the collagen-containing solution having a salt concentration of 1-2M, wherein the dialysis buffer solution and the collagen-containing solution having a salt concentration of 1-2M are conductive, and further wherein; salts from the collagen-containing solution move towards the dialysis buffer solution; and further wherein the contact surface of the porous membrane accelerates the movements of the salts from the collagen-containing solution to the dialysis buffer solution;
2). maintaining the concentration differential between the collagen containing solution and the dialysis buffer solution for three to four days, wherein the dialysis buffer solution is continually recirculated and is changed after 48 hours;
3). monitoring the conductivity of the collagen-containing solution and the dialysis buffer solution until the dialysis buffer (step p1) is completed;
4) ceasing the concentration differential when the collagen-containing solution reaches the same conductivity as the dialysis buffer solution at the commencement of the purification step (step p).) by reaching a conductivity value about 0.20 – 0.28 mS/cm.
q). freezing the purified collagen-containing solution to -40˚C;
r). subjecting the frozen purified collagen-containing solution to a vacuum pressure of 0.04-0.2 mbar (4-20 Pa) for a period of two days, wherein water and solvents are removed in vapor form while drying the collagen structure without damaging the collagen fibers;
s). weighing the resulting collagen;
t). solubilizing to completion the purified collagen-containing solution obtained in step p). in an acid and water solution.
u). transferring the solubilized collagen-containing solution to one or more selected molds, wherein said or more molds have different structures that produce a desired collagen structure of a collagen scaffold, wherein the one or more molds are attached to a plate;
v). lyophilizing for a second time the collagen-containing solution contained in the one or more selected molds at -40˚C;
w). applying vacuum pressure of about 0.04 -0.2 mbar (4-20 Pa);
x). freezing the collagen-containing solution under controlled conditions by slowly removing heat so as to reduce the temperature of the plate on which the one or more molds and collagen-containing solution located therein, causing water and acetic acid to form crystals and forming collagen fibers;
y). depositing the collagen fibers formed in the previous step into a crosslinking apparatus containing a 0.2-1.6 ppm reagent formaldehyde vapor cloud for a duration of about 1-60 minutes, wherein the reagent formaldehyde vapor cloud controlled crosslinking reinforcing bonding between collagen fibers creating a human collagen structure; controlled crosslinking reinforcing bonding between collagen fibers creating a human collagen structure;
wherein the human collagen structures are porous and have an interconnected architecture suitable for supporting adhesion and promoting the cultivation and co-cultivation of primary or established human cell lines and combinations thereof; and further wherein growth factors, proteins, exosomes and combinations thereof for use in regenerative therapy are deposited on the human collagen structures.
Claim 2, as filed on 03/16/2026, recites the process to produce human collagen structures with controlled characteristics according to claim 1, further comprising the step of: z). compacting the human collagen structure is subjected to a determined to increase fibrillar density by subjecting the human collagen structure to a mechanical force of about 400 - 5000 N.
Claim 3, as filed on 03/16/2026, recites the process to produce human collagen structures with controlled characteristics according to claim 1, wherein the pressing step generates collagen structures that are 0.01 – 10 mm in size with density of about 1.25 mg/cm3 to 10,000 mg/cm3.
Claim 8, as filed on 03/16/2026, recites the process to produce human collagen structures with controlled characteristics according to claim 1, wherein the pepsin/acid solution used in step i). 1). is comprised of 0.5M acetic acid containing 2.27% pepsin.
Claim 9, as filed on 03/16/2026, recites the process to produce human collagen structures with controlled characteristics according process to produce human collagen structures with controlled characteristics according to claim 1, wherein the dried conditioned tissue sample in acid created in step 5). j). consists of a ratio of 450 mL of acetic acid solution per one g of dried conditioned tissue.
Claim 10, as filed on 03/16/2026, recites the process to produce human collagen structures with controlled characteristics according to claim 1, wherein the acid solution is an acetic acid solution having a concentration of about 2.5-10 mg/ml; and wherein about 2.5 - 10 mg of collagen per one mL of 0.02 - 0.5 M acetic acid is used.
Claim 11, as filed on 03/16/2026, recites the process to produce human collagen structures with controlled characteristics according to claim 1, wherein the rate of the freezing step x). is 0.2˚-5˚C/min.
Claim 12, as filed on 03/16/2026, recites the process to produce human collagen structures with controlled characteristics according to claim 1, wherein the water present in the acid and water solution of step t) has a molarity of about 0.02-0.5M.
Claim 13, as filed on 03/16/2026, recites the process to produce human collagen structures with controlled characteristics according to claim 1, wherein the crystals formed in step x). exhibit well- formed and interconnected pores with a honeycomb-like morphology.
Claim 14, as filed on 03/16/2026, recites the process to produce human collagen structures with controlled characteristics according to claim 1, wherein the compacted human collagen structure is about 0.01 - 10 mm.
Applicant’s amendment, filed on 03/16/2026, directs to support throughout the application as originally filed, and asserts that no new matter has been added. See p. 10 paragraph 2 of the remarks. However, the specification as filed and the original claims do not provide sufficient written description of the above underlined limitations.
Claim 1 contains new matter because of the limitation requiring: (a) collecting human collagen-containing tissue samples comprising particles having surface proteins and collagen fibers comprised of collagen molecules, wherein said samples exhibit a high degree of biocompatibility.
The specification as filed and the original claims do not provide support for instant claim 1 step (a). The specification filed 06/16/2023, on p. 8 recites: another objective of the invention is to provide said process to produce human collagen structures with controlled characteristics, which also allows the use of an available, accessible raw material with the highest degree of biocompatibility. See p. 8 lines 15-19. Furthermore, the specification discloses that human collagen is derived from cadaveric tissues or debris from surgical procedures, such as the placenta at the time of childbirth. See p. 2 lines 7-10. The disclosure does not provide support for an active method step of collecting human collagen-containing tissue samples, nor does the specification provide support for human collagen-containing tissue samples that contain surface proteins and exhibit a high degree of biocompatibility.
Claim 1 contains new matter because the disclosure does not provide support for the newly added “about” ranges including: g) pH of the conditioned tissue samples value is about 7-8; m). sieving the resulting solution to a particle size between about 125-850 μm; p)1) a porous membrane having a contact surface and a pore size of about 12-14 kD; p) 4) a conductivity value about 0.20 – 0.28 mS/cm; and a vacuum pressure of about 0.04 -0.2 mbar (4-20 Pa). Claim 2 contains new matter because of the limitation requiring mechanical force of about 400 - 5000 N. Claim 10 contains new matter because of the limitation requiring acetic acid solution having a concentration of about 2.5-10 mg/ml; and wherein about 2.5 - 10 mg of collagen per one mL of 0.02 - 0.5 M acetic acid is used. Claim 14 contains new matter because of the limitation requiring wherein the compacted human collagen structure is about 0.01 - 10 mm.
The specification as filed and the original claims do not provide support for the newly added “about” ranges recited in claims 1, 2, 10, and 14. Original claim 1, filed 06/16/2023, provides support for a series of final washes with distilled water, which allow neutralizing the pH of the tissue to a pH between 7-8 (step b1). There is no disclosure of a pH that is about 7-8 as recited in instant claim 1. Original claim 1, filed 06/16/2023, provides support for a solution that is sieved to a particle size between 125-850 μm (step d). There is no disclosure of a particle size between about 125-850 μm, as recited in instant claim 1. Original claim 1, filed 06/16/2023, provides support for a pore size of 12-14 kD (step e). There is no disclosure of a pore size of about 12-14 kD as recited in instant claim 1. Original claim 1, filed 06/16/2023, provides support for conductivity value of 0.20 – 0.28 mS/cm (step e). There is no disclosure of a conductivity value of about 0.20 – 0.28 mS/cm as recited in instant claim 1. Original claim 1, filed 06/16/2023, provides support for a pressure of 0.04 -0.2 mbar (4-20 Pa) (step f). There is no support for about 0.04 -0.2 as recited in instant claim 1. Original claim 1, filed 06/16/2023, provides support for crosslinking where the collagen pieces are subjected to a formaldehyde vapor atmosphere in a crosslinking apparatus, which allows the exposure time to be set between 1-60 minutes (step h). There is no support for a crosslinking step that includes exposure between about 1-60 minutes as recited in instant claim 1. Original claim 2, filed 06/16/2023, provides support for collagen structure that is subjected to a determined mechanical force of 400-5000N to compact its dimensions to a desired value from 0.01 -10 mm and increase its fibrillar density. There is no support for a mechanical force of about 400-5000N as recited in instant claim 2, or a compacted human collagen structure is about 0.01 - 10 mm as recited in instant claim 14. The specification teaches: molding or second lyophilization, where depending on the application and expected function, a concentration of between 2.5-10 mg/mL is chosen and collagen is solubilized again in an acetic acid solution; where between 2.5 - 10 mg of collagen per mL of acetic acid with a molarity of between 0.02 - 0.5 M are used. See p. 18 lines 13-16. There is no support for a acetic acid solution having a concentration of about 2.5-10 mg/ml; and about 2.5 - 10 mg of collagen per one mL of 0.02 - 0.5 M acetic acid as instantly recited in claim 10.
Claims 1, 8-10 and 12 contain new matter because the amendment broadened the scope of the acid from acetic acid to all acids. Claim 1 step i) 1) requires mixing dried conditioned tissue samples with 0.02-0.5 M acid using a solution of pepsin in acid. This mixture is referred to as the pepsin/acid mixture in claim 1 step i)1) and in claim 8. Claim 1 steps j), k) and l) require a conditioned tissue sample acid solution. Claim 9 refers to the tissue sample in acid. Claim 1 step t) requires solubilizing the collagen-containing in an acid and water solution. Claim 12 refers to the acid and water solution of claim 1 step t). Furthermore, claim 10 refers to an acid solution in claim 1.
The specification as filed and the original claims do not provide support for the breadth encompassed by the term “acid” recited in claims 1, 8-10 and 12. Original claim 1 recites subjecting the tissue to an acid solution of acetic acid at a molar concentration of 0.02-0.5 M and using 450L per kg of dry tissue together with 200g of pepsin per kg dry tissue (2.27% pepsin in 0.5 M acetic acid) to promote faster solubilization…adding intermediate acid solution, starting with 200 mL of acetic acid per g of dry tissue and after 48 hours 250 mL of acetic acid per g of dry tissue are added. See step c of original claim 1, which can also be found verbatim on p. 10 of the specification lines 17-24. Therefore, the disclosure only provides support for acetic acid, not all acids.
Claim 1 contains new matter because of the limitation requiring: j). creating a salt concentration greater than 0.5 M.
The specification as filed and the original claims do not provide support for claim 1 step j) creating salt concentrations greater than 0.5 M. Original claim 1, filed 06/16/2023, provides support for precipitation, where the resulting collagen solution is brought to a high salt concentration by adding sodium chloride at a rate of 58.44 g of sodium chloride per L of collagen solution (step d).
Claim 1 contains new matter because of the limitation requiring: u) one or more molds attached to a plate.
The specification as filed and the original claims do not provide support for claim 1 step u) where one or more molds are attached to a plate. Original claim 1, filed 06/16/2023, provides support for placing solubilized collagen in molds that allow to generate the desired structure; once again, the solution is lyophilized at a temperature of -40°C and a vacuum pressure of between 0.04 - 0.2 mbar (4 -20 Pa), with the exception that a controlled freezing is carried out (which consists of removing heat by gradually lowering the temperature of the plate with which the mold and collagen solution are in contact, allowing the water and acetic acid crystals to be uniform and varied accommodating fibers) (step g). The sp
Claim 1 contains contain new matter because of the limitation requiring: y) human collagen structures that are porous and have an interconnected architecture suitable for supporting adhesion; and further wherein growth factors, proteins, exosomes and combinations thereof for use in regenerative therapy are deposited on the human collagen structures.
The specification as filed and the original claims do not provide support for claim 1 step y) human collagen structures that are porous and have interconnected architecture suitable for supporting adhesion. The specification teaches producing human collagen structures with controlled characteristics, which allows the elaboration of collagen structures with adjustable physical characteristics for a wide range of biological applications, by means of simple and low-cost techniques that allow the optimization of collagen concentration in the structures; such characteristics include the dimensions of the structure, fibrillar density, porosity and pore size, which strongly influence cell behavior. See p. 8 lines 21-27. Furthermore, the specification teaches human collagen structures obtained by the described process that are also characterized in that they function as a primary and/or line human cells, and they function as a deposit of growth factors, proteins and exosomes, for their possible use in regenerative therapy. See p. 12 line 25 to p. 13 line 1. As such, the specification does not provide support for an active step of depositing growth factors, proteins, exomes and combinations thereof on human collagen structures as claimed.
Claim 3 contains contain new matter because of the limitation requiring: the pressing step generates collagen structures that are 0.01 – 10 mm in size with density of about 1.25 mg/cm3 to 10,000 mg/cm3.
The specification as filed and the original claims do not provide support for the required density of claim 3. Original claim 2, filed 06/16/2023, provides support for collagen structure that is subjected to a determined mechanical force of 400-5000N to compact its dimensions to a desired value from 0.01 -10 mm and increase its fibrillar density. There is no support for collagen structures that are 0.01 – 10 mm in size with density of about 1.25 mg/cm3 to 10,000 mg/cm3.
Claim 11 contains contain new matter because of the limitation requiring: the rate of the freezing step x). is 0.2˚-5˚C/min.
The specification as filed and the original claims do not provide support for the required freezing rate of claim 11. Original claim 1 provides support for freezing carried out (which consists of removing heat by gradually lowering the temperature of the plate with which the mold and collagen solution are in contact, allowing the water and acetic acid crystals to be uniform and varied, accommodating the fibers). See step g. There is no support for a specific freezing rate.
Claim 11 contains contain new matter because of the limitation requiring: water present in the acid and water solution of step t) to have a molarity of about 0.02-0.5M.
The specification as filed and the original claims do not provide support for water and acid solution required in claim 11. Original claim 1 teaches 2.5-10 mg/mL of collagen per mL of acetic acid with a molarity of between 0.2-0.5M. See step g. The specification teaches an extraction where enzymatic hydrolysis is performed by subjecting the tissue to an acid solution of acetic acid at a molar concentration of 0.02 - 0.5 M. See p. 17 lines 3-4. There is no support for water present in the acid and water solution that has a molarity of about 0.2-0.5M.
Claim 13 contains contain new matter because of the limitation requiring: the crystals formed in step x). exhibit well-formed and interconnected pores with a honeycomb-like morphology.
The specification as filed and the original claims do not provide support for crystal structure required in claim 13. The specification teaches removing heat by gradually lowering the temperature of the plate with which the mold and collagen solution are in contact, allowing the water and acetic acid crystals to be uniform and varied, accommodating the fibers) to generate an estimated average pore size. See p. 18 lines 19-23. There is absolutely no support for a crystal that exhibits well-formed and interconnected pores with a honeycomb-like morphology.
Such limitations recited in the instant claim 1 (and dependent claims), which did not appear in the specification or original claims, as filed, introduce new concepts and violate the description requirement of the first paragraph of 35 U.S.C 112. Applicant is required to provide sufficient written support for the limitations recited in the instant claims. Applicant can remove the new matter limitations from the claims to obviate this rejection.
Claim Rejections - 35 USC § 112(b)
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 1-5, and 7-14 are 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 recites “high” in part a), which renders the claim indefinite. The relative term “high” is not defined by the claims, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Claim 1 requires “a high degree of biocompatibility” (line 5), but it is unclear which degrees of biocompatibility are considered to be high degrees of biocompatability because the term “high” is not defined in the claim or by the specification.
A broad limitation together with a narrow limitation that falls within the broad limitation (in the same claim) may be considered indefinite if the resulting claim does not clearly set forth the metes and bounds of the patent protection desired. See MPEP § 2173.05(c). In the present instance, claim 1 recites the broad recitations “acid”, “pepsin in acid” and “the pepsin/acid solution” in part h).1)., and the claim also recites “pepsin/acetic acid solution” in part h).2). which is the narrower statement of the limitation. The claim(s) are considered indefinite because there is a question or doubt as to whether the feature introduced by such narrower language is (a) merely exemplary of the remainder of the claim, and therefore not required, or (b) a required feature of the claims. In the instant case, it is unclear whether the acid in the pepsin solution is limited to acetic acid.
Claim 1 recites “;,to promote the” in part h).4). right before h).5)., which renders the claim indefinite because the statement is unfinished. Therefore, it is unclear whether the claim is complete. To obviate this rejection, “, to promote the” can be deleted from h).4).
Claim 1 recites “commencement of the purification step (step p).)”, in part p).4). which renders the claim indefinite because it is unclear which purification step is being referenced. Step p requires purifying the collagen-containing solution by employing multiple steps including steps 1-4. Since part p).4). recites “the purification step” in the singular form, it is unclear which singular purification step is being referenced.
Claim 1 recites “mS/cm.” in step p).4), which renders the claim indefinite because in one interpretation claim 1 ends after step p).4). due to the period, and under an alternative interpretation the period at the end of p).4) is a minor informality. As such, it is unclear whether the limitations following the period are required. Furthermore, claim 1 was amended to include a period after the term “solution” in step t), which renders the claim indefinite because it is unclear whether the steps following step t) are required.
Claim 1 recites “lyophilizing for a second time the collagen-containing solution contained in the one or more selected molds” in step v), which is indefinite because there was no earlier requirement for a lyophilization step. Therefore, it is unclear whether step v) requires two lyophilization steps or one.
Claim 1 recites the term “slowly” in step x). which renders the claim indefinite, because the term is not defined by the claims, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention.
Claims 2-5, and 7-14 depend from claim 1 and are rejected for the reasons set forth above.
Claims 1, 2, 3, 10, 12 and claim 14 recite the term “about”, which is a term of approximation. See claim 1 in parts f), m), p).1), p).(4), (w), and (y); claim 2 in the last line; claim 3 in the last line; claim 10 in line 3; claim 12 line 3; and claim 14 in the last line. The specification does not define the term and the specification does not provide any values, such that one of ordinary skill in the art could ascertain the values. Therefore, the amount of permissible variation is unclear. Consequently, one of ordinary skill in the art cannot ascertain the metes and bounds of the claimed range.
Claims 4-5, 7-9, 11, and 13 depend from claim 1 and are rejected for the reason set forth above.
Claim 3 depends from claim 1 and recites “the pressing step” in lines 2-3. There is insufficient antecedent basis for this limitation in the claim. Claim 1 does not require a pressing step, so it is unclear which step is being referenced in claim 3.
Claim 6 recites “the collagen obtained allows the cultivation and co-cultivation of primary and/or line human cells”, which is indefinite because the way in which the collagen obtained “allows” for such cultivation and co-cultivation is unclear. The specification does not describe any particular structure associated with the ability to allow for such cultivation and co-cultivation.
Claim 9 recites “tissue sample in acid created in step 5). j).”, which renders the claim indefinite because there is no step 5). j). in claim 1. Therefore, it is unclear whether claim 9 is referencing the tissue sample acetic acid solution in step h)5), or the conditioned tissue sample acid solution of step j).
Claim 10 recites “the acid solution”, which renders the claim indefinite because it is unclear whether the acid solution is referring to the pepsin in acid in step i)1)m, the acetic acid in i)3), the acid in step i)4), the acetic acid solution in step o), the acetic acid solution in step p)1), the acid and water solution in step t).
Claim 11 recites “the rate of the freezing step x). is 0.2˚-5˚C/min” in lines 2-3, which renders the claim indefinite for two reasons. The first reason is that it is unclear whether the 0.2˚ in 0.2˚-5˚C/min is referring to 0.2˚F or 0.2˚C. The second reason is that it is unclear whether the temperature is required to go up, down or be maintained at 0.2˚-5˚C/min. Since the claim explicitly recites a positive numerical range “0.2˚-5˚C/min”, the claim could reasonably be interpreted as +0.2˚ to +5˚C/min. However, this would contradict the claimed freezing step x) of claim 1, which requires removing heat.
Claim 12 recites “water present in the acid and water solution of step t) has a molarity of about 0.02-0.5M”, which is indefinite because it is not entirely clear whether the water or acid is required to be at a molarity of about 0.2-0.5M. Molarity is moles of solute per liter of solution. For an acid and water solution, the water is understood to be the solution. However, the claim reads as if the water is required to be at a molarity of about 0.2-0.5M.
Claim 13 recites “honeycomb-like morphology” in line 3, which renders the claim indefinite because it is unclear which morphologies constitute as being honeycomb-like. No description is provided in the specification.
Response to Arguments
Applicant's arguments filed 03/16/2026 have been fully considered to the extent that they apply to the new grounds of rejection under 35 U.S.C. 112(b) set forth above, but they are not persuasive. Applicant argues that the term “about” has been defined in the specification as “±5%” to better clarity. See the remarks p. 11 third bullet point.
This argument is unpersuasive because the definition of the term “about” added to the specification 03/16/2026 constitutes as new matter, and 35 CFR 1.121(f) states that no amendment may introduce new matter into the disclosure of an application.
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.
Claims 1, 3-5, and 7-13 are rejected under 35 U.S.C. 103 as being unpatentable over Karami (World J Plast Surg. 2019 Sep;8(3):352-358), Tayot (US 5,436,135), He (Journal of Food Process Engineering, 42(6), e13214, as previously relied upon), Play (US 4,511,653), Jin (KR20180028229A), Nalinanon (Journal of the Science of Food and Agriculture, 90(9), 1492-1500, as previously relied upon), Rodriguez-Rivera, (V.(2014), Doctoral dissertation), and Yannas (US 4,448,718).
Claim interpretation: according to the instant specification human collagen is derived from cadaveric tissues or debris from surgical procedures, such as the placenta at the time of birth. See p. 2 lines 8-9.
Regarding claim 1, Karami teaches extracting collagen from human placenta. See the abstract.
a) Karami teaches obtaining (i.e. collecting) human placenta was from a hospital. See p. 353 left column last passage.
b) Karami teaches removing residual blood (i.e. fluids from the human collagen-containing tissue samples) and cleaning samples. See p. 353 right column first passage.
c) Karami teaches chopping washed samples to 1-2 cm. See p. 353 right column first paragraph.
Karami does not teach reducing the size of desired particles of collagen to 0.5 to 1 mm to create a uniform conditioned tissue sample.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to optimize the size of the placenta samples of Karami. One of ordinary skill in the art would have been motivated to do so because Karami suggests reducing the size of the particles by chopping. There would have been a reasonable expectation of success because Karami provides a starting size from which one of ordinary skill in the art could reasonably optimize. MPEP 2144.05(II)(A) states that “[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation."
d) Karami teaches mixing placenta with 0.1 N NaOH (0.1 M) at a sample/alkali solution ratio of 1:10 (w/v). See p. 353 right column first paragraph.
Karami does not teach a sodium hydroxide molar concentration of 0.5-2M using a ratio of 100 mL of sodium hydroxide solution per one gram of dried conditioned tissue sample.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to optimize the sample to NaOH ratio of Karami. One of ordinary skill in the art would have been motivated to do so because Karami suggests mixing placenta in a solution ratio with sodium hydroxide. There would have been a reasonable expectation of success because Karami provides a starting ratio from which one of ordinary skill in the art could reasonably optimize. MPEP 2144.05(II)(A) states that “[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation."
e) Karami teaches mixing placenta with NaOH and stirring the mixture for 6 hours. See p. 353 right column first paragraph.
Karami and Tayot do not teach using magnetic agitation.
He teaches extracting collagen from fishbone. See the abstract. He teaches mixing fish-bone samples uniformly with magnetic stirrer. See section 2.5.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to apply He’s magnetic agitation to Karami’s conditioned placenta sample and sodium hydroxide solution. One of ordinary skill in the art would have been motivated to do so because He suggests that the magnetic stirring (i.e. agitation) is uniform. There would have been a reasonable expectation of success because Karami demonstrates mixing placenta with sodium hydroxide for 6 hours, which is within the instantly claimed 2-6 hours range.
f) Karami teaches changing the alkali solution (i.e. a removal of excess sodium hydroxide). See p. 353 right column first paragraph.
g) Karami teaches washing samples with distilled water. See p. 353 right column first paragraph. Karami also teaches a final solution pH =7, which is a pH of about 7-8 as instantly required. See p. 353 right column second paragraph.
h) Karami teaches rinsing samples with distilled water and filtering the solution with cheese cloth (i.e. drying). Karami also teaches precipitating the solution, centrifuging the precipitate and discarding the supernatant (i.e. a drying). See p. 353 right column second paragraph.
i) Karami suggests that collagen can be extracted by enzymatic hydrolysis. See p. 353 right column paragraph 2.
i1) Tayot teaches washing placental tissue. See column 7 line15. Tayot discloses that the weight obtained is 82 kg. See column 7 line 18. Then, Tayot teaches subjecting it to enzymatic digestion with pepsin in 500 l of 0.05M citric acid containing 300 g of pepsin. See column 7 lines 19-21.
Karami, Tayot and He do not teach a ratio of 200 g of the pepsin/acid solution for each kg of dried conditioned tissue samples used, wherein specific and controlled removal of terminal carboxy and amino groups of the conditioned tissue samples occurs.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to apply Tayot’s enzymatic hydrolysis to Karami’s dried tissue sample, and to further optimize the ratio of Tayot’s pepsin/citric acid solution to the kg of dried tissue sample; and in the process any terminal carboxyl and amino groups would be necessarily removed. One of ordinary skill in the art would have been motivated to apply the enzymatic hydrolysis of Tayot because Karami suggests that chemical hydrolysis is used more in industry, but biological procedures which use enzymes are more helpful (p. 353 left column second paragraph). There would have been a reasonable expectation of success because Tayot demonstrates applying the enzymatic hydrolysis to placental tissue. One would have been further motivated to optimize the ratio of the pepsin/acid solution to kg dried tissue sample, because a person of ordinary skill in the art has good reason to pursue the known options within their technical grasp. There would have been a reasonable expectation of success because Tayot teaches a starting ratio of 300g pepsin per 82kg sample from which one could optimize. MPEP 2144.05(II)(A) states that “[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation."
i2) Tayot teaches subjecting the sample to enzymatic digestion with pepsin and citric acid. See column 7 line 19. The tissue residue containing the essential non-solubilized collagens I and III are separated by means of centrifuge (i.e. removal of excess pepsin/acid and drying).
i3) Tayot suggests subjecting residues to a second enzymatic digestion. See column 7 line 29-30.
Karami, Tayot and He do not teach adding an intermediate acid solution, comprising 200 mL of acetic acid per g dried conditioned tissue samples.
Play teaches preparing collagenous materials from human placental tissues. See column 1 lines 9-10. In example 2, teaches placing 20kg residue in 100 liters of 0.5M acetic acid (i.e. 143.12 mL acetic/kg residue) containing pepsin. After 24 incubation, insoluble residues are eliminated by centrifugation. See column 5 lines 3-6.
Karami, Tayot, He and Play do not teach 200 mL of acetic acid per g dried conditioned tissue samples.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to apply Play’s acetic acid to the enzymatically hydrolyzed tissue samples of Karami, Tayot and He, and to further optimize the acetic acid per each gram of dried conditioned tissue samples. One of ordinary skill in the art would have been motivated to apply Play’s acetic acid solution to the enzymatically hydrolyzed tissue samples of Karami, Tayot and He, because Tayot suggests subjecting residues to a second enzymatic digestion. There would have been a reasonable expectation of success because Play demonstrates applying the acetic acid and pepsin to placenta tissue samples in example 2. See Play column 4 line 30 for the disclosure that the residues in example 2 are from placenta. One of ordinary skill in the art would have been further motivated to optimize the acetic acid per g because a person of ordinary skill in the art has good reason to pursue the known options within their technical grasp. There would have been a reasonable expectation of success because Play demonstrates 143.12 mL acetic/kg residue, from which one could reasonably optimize. MPEP 2144.05(II)(A) states that “[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation."
i4) Play, in example 2, teaches placing 20kg residue in 100 liters of 0.5 acetic acid (i.e. 143.12 mL acetic/kg residue) containing pepsin. After 24 incubation, insoluble residues are eliminated by centrifugation. See column 5 lines 3-6. Play suggests that treating the residue with an alkaline solution then a dilute acid solution inactivates hepatitis virus. See column 3 lines 24-31.
Karami, Tayot, He and Play do not teach after 48 hours, adding 250 mL of acetic acid per g dried conditioned tissue samples.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to repeat the acetic acid addition of Play and to further optimize the acetic acid per each gram of dried conditioned tissue samples. One of ordinary skill in the art would have been motivated to re-apply Play’s acetic acid solution because Play suggests that it may inactivate hepatitis. There would have been a reasonable expectation of success because Play demonstrates applying the acetic acid and pepsin to placenta tissue samples in example 2. One of ordinary skill in the art would have been further motivated to optimize the acetic acid per g because a person of ordinary skill in the art has good reason to pursue the known options within their technical grasp. There would have been a reasonable expectation of success because Play demonstrates 143.12 mL acetic/kg residue, from which one could reasonably optimize. MPEP 2144.05(II)(A) states that “[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation."
i5) Play, in example 2, teaches concentrating pepsic extract by ultrafiltration. See column 5 line 10. Furthermore, Play teaches subjecting the solution to chromatography, such that the non-retained fraction contains the collagens (i.e. removal of residues of non-collagenous tissue structures). The non-retained fraction is equilibrated in 50 liters of 0.5M acetic acid. See column 5 lines 14-18.
j) Play teaches adding increasing quantities of NaCl to the solution and precipitating collagens types IV and V at a concentration of 1.2 M (i.e. 1.2 mol per liter of the sample in acetic acid solution). See column 5 lines 19-23. As such, Play suggests adding NaCl at a rate of 70.13 grams per liter, because 1.2 mol/L x 58.44 g/mol (i.e. molar mass of NaCl)=70.13.
Karami, Tayot, He and Play do not teach adding sodium chloride at a rate of 58.44 g of sodium chloride per 1 liter of treated, conditioned tissue sample acid solution.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to optimize NaCl molarity and in the process optimize the rate of sodium chloride added per liter. A person of ordinary skill in the art has good reason to pursue the known options within their technical grasp. There would have been a reasonable expectation of success because Play demonstrates precipitating collagen at a rate of 70.13 grams per liter. MPEP 2144.05(II)(A) states that “[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation."
k) Play teaches successive redissolutions (i.e. homogenizing) and saline reprecipitations to improve purification. See column 5 lines 24-25.
Karami, Tayot, and Play do not teach homogenizing using magnetic stirring.
He teaches extracting collagen from fishbone. See the abstract. He teaches mixing with a magnetic stirrer. See section 2.5.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to apply He’s magnetic agitation to the homogenized collagen of Karami, Tayot and Play. One of ordinary skill in the art would have been motivated to do so because He suggests that the magnetic stirring is uniform. There would have been a reasonable expectation of success because Play demonstrates redissolving, i.e. homogenizing, samples after an NaCl precipitation.
l) Karami teaches stirring for 6 hours. See p. 353, right column paragraph 1.
Play teaches adding NaCl to a chromatography fraction containing collagen and acetic acid in order to precipitate collagen. See column 5 lines 18-20. In order to improve purification, successive redissolutions (i.e. homogenizing) and saline reprecipitations can be carried out. See column 5 lines 24-25.
Karami, Tayot, He and Play do not teach precipitating by continually stirring for 2-6 hours.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to combine Karami’s stirring and Play’s precipitation. One of ordinary skill in the art would have been motivated to do so because Play suggests improving the precipitation of collagen. There would be a reasonable expectation of success because Play demonstrates precipitating collagen and Karami demonstrates stirring for 6 hours.
m-n) Tayot teaches recovering collagen fibers by filtration through sieve. The fibers are dried. See column 5 lines 10-12.
Karami, Tayot, He and Play do not teach sieving the resulting solution to a particle size of about 125-850 µm (relevant to instant part m).
Jin teaches producing highly biocompatible human-derived collagen. See [0050]. Jin teaches passing acellular allogenic dermis through a 250 µm sieve. See [0055].
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to apply Tayot’s sieving and recovery to the collagen of Karami as modified by Tayot, Play, and He, and to further substitute Jin’s 250 µm sieve for Tayot’s sieve and in the process necessarily arrive at a 250 µm particle size, which is about 125-850 µm as instantly required. One of ordinary skill in the art would have been motivated to do so because Jin suggests using a 250 µm sieve to produce highly biocompatible human-derived collagen. There would have been a reasonable expectation of success because Karami and Tayot teach extracting collagen from human placenta, Tayot demonstrates sieving collagen fibers and Jin teaches a 250 µm sieve.
o) Karami teaches redissolving in 2% acetic acid. See p. 353 right column second paragraph.
Tayot teaches recovering collagen fibers by filtration through sieve, and drying the fibers. See column 5 lines 10-12. The purified collagen precipitate is redissolved in water. See column 5 lines 18-19.
Karami, Tayot, He, Play and Jin do not teach solubilizing the dried recovered collagen fibers in an acetic acid solution having a ratio of 350 mL acetic acid per one g of dried conditioned tissue creating a collagen-containing solution.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to redissolve the sieved and recovered collagen as taught by Tayot, to further combine the water used in the redissolution with acetic acid, and to further optimize the amount of acetic acid. One of ordinary skill in the art would have been motivated to combine the water for redissolution with acetic acid, because Karami suggests redissolving collagen in acetic acid. There would have been a reasonable expectation of success because Tayot demonstrates redissolving collagen in water after sieving and recovering the collagen, and Karami demonstrates redissolving collagen in acetic acid. One of ordinary skill in the art would have been further motivated to optimize the amount of acetic acid because Karami suggests 2% acetic acid. There would have been a reasonable expectation of success Karami provides a starting amount from which one could optimize.
p-p1) Karami teaches dissolving collagen precipitate in 2% acetic acid and transferring it to dialysis tubing cellulose membranes and stirring in distilled water refreshed every 8 h for 5 days. See p. 353 right column second paragraph.
Karami, Tayot, Play, He and Jin do not teach pouring the collagen-containing solution into a porous membrane having a contact surface and a pore size of about 12-14 kD, wherein the porous membrane removes impurities from the collagen-containing solution when the collagen-containing solution is introduced into a dialysis buffer solution consisting of 0.02 – 0.5 M acetic acid, wherein salt molecules in the collagen-containing solution having a salt concentration of 1-2M and the dialysis buffer solution are exchanged due to a concentration differential between the dialysis buffer solution and the collagen-containing solution having a salt concentration of 1-2 M, wherein the dialysis buffer solution and the collagen-containing solution having a salt concentration of 1-2M are conductive, and further wherein; salts from the collagen-containing solution move towards the dialysis buffer solution; and further wherein the contact surface of the porous membrane accelerates the movements of the salts from the collagen-containing solution to the dialysis buffer solution;
Nalinanon teaches extracting collagen from prepared the skin. Nalinanon teaches combining the supernatant from a centrifuged solution of skin and acetic acid with NaCl to obtain a final concentration of 2.6 mol/L in Tris-HCl. The resultant precipitate is collected by centrifugation. The pellet is dissolved in acetic acid and the solution obtained is dialyzed against 0.1 mol/L acetic acid (i.e. a dialysis buffer consisting of 0.02-0.5M acetic acid) in a dialysis bag with a molecular weight cut-off of 14 kDa for 12 hours, with a change of dialysis solution every 4 hours. See the last paragraph on page 2 and the paragraph spanning pages 2-3.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to apply Nalinanon’s dialysis to the collagen-containing sample of Karami, Tayot, Play, He and Jin, and to further optimize the salt concentration. One of ordinary skill in the art would have been motivated to apply Nalianon’s dialysis because Nalinanon suggests that the dialysis can be used to extract collagen. There would have been a reasonable expectation of success because Karami and Nalinanon demonstrates dialyzing collagen containing solutions. One would be further motivated to optimize the salt concentration, because a person has good reason to pursue the known options within their technical grasp. There would have been a reasonable expectation of success because Nalinanon provides a 2.6 M NaCl from which one could reasonably optimize. MPEP 2144.05(II)(A) states that “[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation."
p2) Karami teaches a dialysis that includes stirring in distilled water refreshed every 8 h for 5 days. See p. 353 right column second paragraph. Therefore, Karami suggests a continuous recirculation and changing after 48 hrs.
Nalinanon teaches a dialysis in which the dialysis solution is changed every 4 hours. See the last paragraph on page 2 and the paragraph spanning pages 2-3.
Karami, Tayot, Play, He, Jin and Nalinanon do not teach maintaining the concentration differential between the collagen containing solution and the dialysis buffer solution for three to four days.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to optimize the timespan of the dialysis. A person of ordinary skill in the art has good reason to pursue the known options within their technical grasp. There would have been a reasonable expectation of success because Karami teaches a 5 day timespan from which one could optimize. MPEP 2144.05(II)(A) states that “[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation."
p3) Nalinanon teaches measuring (i.e. monitoring) conductivity in mS cm-1. See figure 2A and B.
p4) Nalinanon teaches measuring the conductivity. See figure 2A and B.
Karami, Tayot, Play, He, Jin and Nalinanon do not teach ceasing the concentration differential when the collagen containing solution reaches the same conductivity as the dialysis buffer solution at the commencement of the purification step by reaching a conductivity value between about 0.20 - 0.28 mS/cm.
Rodriguez-Rivera teaches precipitating and dialyzing collagen. The water is continually changed until the conductivity reaches 50µS/cm (i.e. 0.05 mS/cm). See p. 31 section 2.3.1.7. Rodriguez-Rivera discloses that a conductivity of 50µS/cm is equivalent to a salt concentration of 500 mM. See p. 39 last line.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to further modify Nalinanon’s dialysis based on Rodriguez-Rivera’s suggestion. One would have been motivated to do so because Rodriguez-Rivera’s suggests that conductivity is indicative of salt concentration. There would have been a reasonable expectation of success because Nalinanon demonstrates measuring conductivity during the dialysis.
q) Karami teaches dialyzing and finally freeze-drying samples. See p. 353 right column paragraph 2.
Jin teaches freeze-drying at a temperature of -40˚C. See [0054].
r) He teaches vacuum freeze-drying (i.e. 2 days) collagen samples for 48h to obtain powdery samples. See section 2.8.
Karami, Tayot, Play, He, Jin, Nalinanon and Rodriguez-Rivera do not teach a vacuum pressure of 0.04-0.2 mbar.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to apply the vacuum freeze-drying of He and to further optimize the vacuum pressure. One would have been motivated to do so because He suggests that the vacuum freeze-drying obtains powdery samples. There would have been a reasonable expectation of success because He demonstrates vacuuming, which necessitates a vacuum pressure.
s) Rodriguez-Rivera teaches lyophilizing a sample and weighing it. See p. 32 section 2.3.2.
t) Jin teaches mixing a solution of freeze-dried collagen dissolved in saline solution with 2% hyaluronic acid (i.e. acid and water solution). See [0022].
u) Jin teaches mixing a solution of freeze-dried collagen dissolved in saline solution with 2% (w/v) hyaluronic acid, and then treating with a crosslinking agent to prepare a mixture; injecting the mixture into a cylindrical mold to carry out a crosslinking. See [0022].
Rodriguez-Rivera teaches cylindrical molds that are a six well plate (i.e. mold attached to a plate). See p. 90 section 4.3.2.1.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to apply Jin’s water and acid solubilization and mold transfer steps of Jin to the collagen-containing solution, and to further substitute the mold of Jin for the mold attached to the plate of Rodriguez-Rivera. A person of ordinary skill in the art has good reason to pursue the known options within their technical grasp. There would have been a reasonable expectation of success because the molds serve the same function.
v) Jin teaches injecting the mixture into a mold, crosslinking and freeze-drying the mixture after crosslinking. See [0022]. Jin teaches freeze-drying at a temperature of -40˚C. See [0054].
w) He teaches vacuum freeze-drying (i.e. 2 days) collagen samples for 48h to obtain powdery samples. See section 2.8.
Karami, Tayot, Play, He, Jin, Nalinanon and Rodriguez-Rivera do not teach a vacuum pressure of 0.04-0.2 mbar.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to apply the vacuum freeze-drying of He and to further optimize the vacuum pressure. One would have been motivated to do so because He suggests that the vacuum freeze-drying obtains powdery samples. There would have been a reasonable expectation of success because He demonstrates vacuuming, which necessitates a vacuum pressure.
x) Jin suggests freeze-drying in the mold. See [0022]. Jin teaches freeze-drying at a temperature of -40˚C. See [0054].
Although Karami, Tayot, Play, He, Jin, Nalinanon and Rodriguez-Rivera do not teach causing water and acetic acid to form crystals and forming collagen fibers, based on the instantly claimed language Jin’ freezing step necessarily removes heat and reduces temperature which causes such crystals and fibers to form.
y) Jin teaches mixing a solution of freeze-dried collagen dissolved in saline solution with 2% (w/v) hyaluronic acid, and then treating with 4% (v/v) crosslinking agent BDDE (1,4-Butanediol diglycidyl ether) to prepare a mixture; injecting the mixture into a cylindrical mold to carry out a crosslinking reaction for 5 hours. See [0022].
Karami, Tayot, Play, He, Jin, Nalinanon and Rodriguez-Rivera do not teach y). depositing the collagen fibers formed in the previous step into a crosslinking apparatus containing a 0.2-1.6 ppm reagent formaldehyde vapor cloud for a duration of about 1-60 minutes, wherein the reagent formaldehyde vapor cloud controlled crosslinking reinforcing bonding between collagen fibers creating a human collagen structure; controlled crosslinking reinforcing bonding between collagen fibers creating a human collagen structure; wherein the human collagen structures are porous and have an interconnected architecture suitable for supporting adhesion and promoting the cultivation and co-cultivation of primary or established human cell lines and combinations thereof; and further wherein growth factors, proteins, exosomes and combinations thereof for use in regenerative therapy are deposited on the human collagen structures.
Yannas teaches crosslinking collagen-glycosaminoglycan composite materials using gaseous aldehydes to produce a crosslinked product suitable for use as an artificial skin. See column 2 lines 64-66. Yannas teaches collagen dispersed in acetic acid to which hyaluronic acid is added. See column 7 lines 17-19. Yannas teaches, in example 6, vapor crosslinking collagen-glycosaminoglycan composites in formaldehyde. See column 10 line 33-34. Yannas teaches pouring 60 mL formaldehyde into a desiccator (i.e. crosslinking apparatus containing formaldehyde vapor) . See column 10 lines 35-36. Yannas teaches a highly porous lattice (i.e. interconnected architecture) comprising collagen crosslinked with glycosaminoglycan. The lattice is a biophysical supporting structure in which cells can migrate and proliferate to heal a wound (i.e. promoting the cultivation and co-cultivation of primary or established human cell lines). See column 1 lines 24-28. Therefore, Yannas indicates that cells (i.e. containing proteins) migrate (i.e. deposit) on the structure.
Karami, Tayot, Play, He, Jin, Nalinanon, Rodriguez-Rivera and Yannas do not teach 0.2-1.6 ppm reagent formaldehyde vapor cloud.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to apply Yannas’s formaldehyde vapor crosslinking to the collagen-containing sample of Karami, Tayot, Play, He, Jin, Nalinanon, Rodriguez-Rivera; and to further optimize the concentration of the formaldehyde vapor. One of ordinary skill in the art would have been motivated to apply the formaldehyde vapor crosslinking because Yannas suggests that the gaseous aldehydes diffuse freely through pores of the porous collagen-glycosaminoglycan composite materials. There would have been a reasonable expectation of success because Yannas demonstrates a formaldehyde vapor crosslinking with collagen. One would have been motivated to optimize the formaldehyde vapor, because a person of ordinary skill in the art has good reason to pursue the known options within their technical grasp. There would have been a reasonable expectation of success because Yannas provides a starting amount from which one could optimize. MPEP 2144.05(II)(A) states that “[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation."
Regarding claim 3, Tayot teaches pressing placenta tissue to separate blood. See column 6 line 63-64.
Yannas teaches sheets of collagen for use as artificial skin. Such sheets generally have a thickness of about 2mm. See column 5 lines 46-48. Yannas teaches a volume fraction, V2, calculation utilizes a 21.3 gr/in3 (i.e. 1299.8 mg/cm3) density of collagen. See column 9 lines 34-36.
Regarding claim 4, Jin teaches increasing the extraction efficiency, and as a result, a high yield of more than 35% can be expected. See [0044].
Regarding claim 5, Jin teaches the collagen content in the extracted collagen sample is 97% or higher, which means that the extracted collagen is of high purity with almost no impurities. See [0074]
Regarding claim 7, Karami teaches extracting collagen from human placenta (i.e. debris from a human surgical procedure). See the abstract. Karami teaches obtaining human placenta was from a hospital. See p. 353 left column last passage.
Regarding claim 8, Play teaches preparing collagenous materials from human placental tissues. See column 1 lines 9-10. In example 2, teaches placing 20kg residue in 100 liters of 0.5M acetic acid (i.e. 143.12 mL acetic/kg residue) containing 100g pepsin. See column 5 lines 3-6.
Karami, Tayot, Play, He, Jin, Nalinanon, Rodriguez-Rivera and Yannas do not teach 2.27% pepsin.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to optimize the percentage of pepsin. A person of ordinary skill in the art has good reason to pursue the known options within their technical grasp. There would have been a reasonable expectation of success because Play provides a starting 100g pepsin (0.1%) in 100L of 0.5 acetic acid from which one could optimize. MPEP 2144.05(II) states that "[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation."
Regarding claim 9, Play teaches preparing collagenous materials from human placental tissues. See column 1 lines 9-10. In example 2, teaches placing 20kg residue in 100 liters of 0.5M acetic acid (i.e. 5mL of 0.5M acetic acid solution per gram residue) containing pepsin. See column 5 lines 3-6.
Karami, Tayot, Play, He, Jin, Nalinanon, Rodriguez-Rivera and Yannas do not teach j) consists of a ratio of 450 mL of acetic acid solution per one g of dried conditioned tissue.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to optimize ratio of acid solution per gram dried conditioned tissue. A person of ordinary skill in the art has good reason to pursue the known options within their technical grasp. There would have been a reasonable expectation of success because Play provides a starting ratio of 5mL/g from which one could optimize. MPEP 2144.05(II) states that "[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation."
Regarding claim 10, Play teaches 20kg residue in 0.5M acetic acid (i.e. 30.03 mg/mL acetic acid) containing pepsin. See column 5 lines 3-6. Therefore, Play indicates that acetic acid is at 30.03 mg/mL acetic acid (i.e. about 2.5-10 mg/mL) because the molarity is 0.5M. Furthermore, Play teaches 20kg residue in 100L of 0.5M acetic acid. See column 5 lines 3-6. Therefore, Play suggests that 20mg per mL of the 0.5M acetic acid (i.e. about 2.5-10 mg per mL of 0.2-0.5 acetic acid).
Regarding claim 11, Jin suggests freeze-drying in the mold. See [0022]. Jin teaches freeze-drying at a temperature of -40˚C or lower for at least 2 hours. See [0054].
Karami, Tayot, Play, He, Jin, Nalinanon, Rodriguez-Rivera and Yannas do not teach 0.2˚- 5 ˚C/min.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to adjust the freezing rate of Jin. A person of ordinary skill in the art has good reason to pursue the known options within their technical grasp. There would have been a reasonable expectation of success because Jin suggests -40˚C for at least 2 hours and -40˚C/120min is -0.333˚C/min.
Regarding claim 12, Jin teaches an acidic solution that may be 0.5 to 2 M, which overlaps with the instantly claimed 0.02-0.05 M range. See [0016].
Regarding claim 13, Jin suggests freeze-drying in the mold. See [0022]. Jin teaches freeze-drying at a temperature of -40˚C. See [0054].
Karami, Tayot, Play, He, Jin, Nalinanon, Rodriguez-Rivera and Yannas do not teach crystals formed in step x) that exhibit well-formed and interconnected pores with a honeycomb-like morphology.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to recognize that the freezing at -40˚C, as taught by Jin, necessarily results in acetic acid crystals that exhibit an interconnected porous structure with honeycomb-like morphology.
Claims 2 and 14 are rejected under 35 U.S.C. 103 as being unpatentable over Karami (World J Plast Surg. 2019 Sep;8(3):352-358), Tayot (US 5,436,135), He (Journal of Food Process Engineering, 42(6), e13214, as previously relied upon), Play (US 4,511,653), Jin (KR20180028229A), Nalinanon (Journal of the Science of Food and Agriculture, 90(9), 1492-1500, as previously relied upon), Rodriguez-Rivera, (V.(2014), Doctoral dissertation), and Yannas (US 4,448,718), as applied to claims 1, 3-5, 7-13 above, and further in view of Hu (Biomedical microdevices, 12(4), 627-635).
Regarding claim 2, Tayot teaches pressing placenta tissue to separate blood. See column 6 line 63-64.
Karami, Tayot, Play, He, Jin, Nalinanon, Rodriguez-Rivera and Yannas do not teach z) compacting the human collagen structure to increase fibrillar density by subjecting the human collagen structure to a mechanical force of about 400-5000 N.
Hu teaches preparing compressed collagen gel. After gel formation, the gel is weighed and then compressed on a bed of absorbent paper bounded by a nylon mesh using a mass of 48 g for 1 min, stress equivalent to approximately 1.1 kN m-2 (i.e. 1,100 N m-2). See section 2.2 and figure 1.
It would have been obvious to a person of ordinary skill in the art prior to the effect filing date of the instantly claimed invention to optimize the pressure of Tayot in view of the 1,100 N m-2 pressure taught by Hu within the method of Karami, Tayot, Play, He, Jin, Nalinanon, Rodriguez-Rivera and Yannas. In the process, one would arrive at a fine and highly dense collagen structure, absent evidence to the contrary. One would be motivated to do so because Hu suggests that the compression of collagen gel can improve its mechanical property. There would be a reasonable expectation of success because MPEP 2144.05(II)(A) indicates that “[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Regarding claim 14, Yannas teaches sheets of collagen for use as artificial skin. Such sheets generally have a thickness of about 2mm, which is about 0.01-10mm as instantly required. See column 5 lines 46-48.
Response to Arguments
Applicant's arguments filed 03/16/2026 have been fully considered but they do not apply to the new grounds of rejection set forth above.
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.
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/LOUISE W HUMPHREY/Supervisory Patent Examiner, Art Unit 1657
/K.C.B./Examiner, Art Unit 1657
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