DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Applicant’s Response to Election/Restriction Filed and Arguments/Remarks, filed 02 July 2025, have been entered. Claims 1-14, 18-19, 22-24, 28, and 31 are currently pending. Claims 1, 13, 18, 22, 23, 24, 28, and 31 are independent claims. Applicant’s election without traverse of the invention of Group I, drawn to a method of generating a stem cell (SC), a stem cell produced by the method, a beta cell produced by the method, a second stem cell, and a cell line derived from the second stem cell, is acknowledged.
Additionally, applicant’s election of the following species:
Genes with reduced expression: a. HLA-1, i. Reduced by: 2. Abrogating expression of β2M;
First exogenous construct expressing genes: a. CR1;
Second exogenous construct expression genes: g. HLA-E single chain trimer;
Exogenous construct introduction: b. AAV construct;
without traverse in a reply filed 02 July 2025 is acknowledged. Upon further consideration, Examiner has withdrawn the species election requirement for 2) First exogenous construct expressing genes and 3) Second exogenous construct expression genes.
Claims 7 and 9 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected species and claims 18-19, 23, and 31 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim.
Claims 1-6, 8, 10-14, 22, 24, and 28 are currently pending in the application and under examination to which the following grounds of rejection are applicable. An action on the merits follows.
Priority
The present application is a 35 U.S.C. 371 national stage filing of International Application No. PCT/US2020/055123, filed 09 October 2020, which claims priority to U.S. provisional Application No. 62/913,568, filed 10 October 2019.
Thus, the earliest possible priority for the instant application is 10 October 2019.
Information Disclosure Statement
The information disclosure statements filed 11 April 2022, 16 January 2024, and 09 July 2025 have been considered by the Examiner. Applicant’s filing of the Assertion under 37 CFR 1.98 on 09 July 2025, indicating that no IDS size fee is required under 37 CFR 1.17(v) at this time, is acknowledged.
Claim Objections
Claims 1-2, 4, and 24 are objected to because of the following informalities: claims 1-2, and 4 recite the abbreviation “CR1” without first writing out the term for which “CR1” is an abbreviation. Appropriate correction is required.
Claim 5 is objected to because of the following informalities: claim 5 recites the abbreviation “PD-L1” without first writing out the term for which “PD-L1” is an abbreviation. Appropriate correction is required.
Claim 6 is objected to because of the following informalities: claim 6 recites the abbreviations “TAP1” and “β2M” without first writing out the term for which ““TAP1” and “β2M” are an abbreviation. Appropriate correction is required.
Claim 11 is objected to because of the following informalities: claim 11 recites the gene “PPPR12C” which appears to be a typographical misspelling of “PPP1R12C”. Claim 11 is additionally objected to for reciting the abbreviation “PPPR12C” without first writing out the term for which “PPPR12C” is an abbreviation. Appropriate correction is required.
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 1-6, 8, 10-14, 22, 24, and 28 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.
Independent claim 1 recites the step of “introducing exogenous constructs to express immune evasion genes”, which is indefinite because it is unclear into what the exogenous constructs are being introduced. As such, the metes and bounds of the claim cannot be determined. Claims 2-6, 8, 10-14, and 22 are included in this rejection due to their dependence on or encompassing of claim 1.
Claims 1 and 24 recite the term “and/or” in lines 5 and 3, respectively. It is unclear what the metes and bounds of this term, as “and” could be interpreted to include only CR1 evasion genes, or all of the evasion genes, or, “or” would imply that the evasion gene types are in the alternative. Appropriate correction is required. Claims 2-6, 8, 10-14, and 22 are also included in the rejection as they directly or indirectly depend on claim 1. Claim 28 is also included in the rejection as it directly depends on claim 24.
Claim 4 is indefinite because of its recitation of “ the immune evasion genes comprise CR1, CD24, CD47, CD55, CD46, and CD59”. It is unclear if the CR1 and CD24 are the same genes that claim 1 recites or different genes. As such the metes and bounds of the claim are indefinite.
Claim 11 recites “a site of endogenous AAV integration”, which is indefinite because it is unclear what the site is endogenous to. As such, the metes and bounds of the claim cannot be determined.
Claim 12 recites the limitation “the SC” in line 2. There is insufficient antecedent basis for this limitation in the claim. Claim 12 is dependent on independent claim 1. Claim 1 recites “a stem cell (SC)” in line 1, “a SC” in line 2, and “a wild-type SC” in line 2. Therefore, it is unclear which SC “the SC” of claim 12 is referring to. As such, the metes and bounds of the claim cannot be determined. Claim 22 is included in this rejection due to its encompassing of claim 12.
Claim Rejections - 35 USC § 102
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 1-3, 5-6, 8, 12-13, 22, 24, and 28 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Schrepfer [US20230025289A1, published 26 January 2023, filed 24 August 2020, with priority to U.S. Provisional Application No. 62/891,180, filed 23 August 2019].
Regarding claims 1-2, 6, and 13 Schrepfer discloses a method of generating a stem cell (SC) comprising a) modifying a SC to reduce expression relative to a wild-type SC of HLA-I by abrogating expression of B2M/β2M [abstract, 0138, 0171-0175, claim 5]; and b) introducing exogenous constructs to express immune evasion genes comprising CR1/CD35 and CD24 [0138, 0160, 0198], and the cell produced by the method.
Regarding claims 3 and 5, Schrepfer further discloses introducing exogenous constructs to express immune evasion genes further comprising one or more of CD47, CD55, CD46, CD59, HLA-E heavy chain, and PD-L1 [0009, 0026, 0038, 0043, 0046, 0048, 0198, claims 3, 22].
Regarding claim 8, Schrepfer teaches wherein the modifying comprises genome editing using CRISPR/Cas9 targeted mutation [0006-0007, 0094, 0116, 0166, 0171, 0174, 0221].
Regarding claims 12 and 22, Schrepfer teaches that the method further comprises differentiating the SC to a β cell [0372-0381].
Regarding claims 24 and 28, Schrepfer teaches a stem cell wherein (i) expression of HLA-I and HLA-II is abrogated; and (ii) the SC is genetically modified to express CR1/CD35 and/or CD24 [0043, 0393, claim 63, 148]. Schrepfer also teaches a cell line derived from the stem cell according to claim 24 (e.g., cultured B2M-/-CIITA-/-CD24tg hiECs) [0393-0395].
Accordingly, by teaching all of the limitations of claims 1-6, 8, 12-13, 22, 24, and 28, Schrepfer anticipates the instant invention as claimed.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 1, 4, 10, 11 and 14 are rejected under 35 U.S.C. 103 as being unpatentable over Schrepfer [US20230025289A1, published 26 January 2023, filed 24 August 2020, with priority to U.S. Provisional Application No. 62/891,180, filed 23 August 2019]; in view of Oceguera-Yanez et al. [2016, Methods, 101, 43-55, published online 18 December 2015]; and Gornalusse et al. [2017, Nature Biotechnology, 35(8), 765-775].
Regarding claim 1, Schrepfer discloses a method of generating a stem cell (SC) comprising a) modifying a SC to reduce expression relative to a wild-type SC of HLA-I by abrogating expression of B2M/β2M [abstract, 0138, 0171-0175, claim 5]; and b) introducing exogenous constructs to express immune evasion genes comprising CR1/CD35 and CD24 [0138, 0160, 0198], and the cell produced by the method.
Regarding claim 4, Schrepfer does not explicitly teach wherein the immune evasion genes comprise CR1/CD35, CD24, CD47, CD55, CD46, and CD59.
However, given the teaching of Schrepfer to introduce exogenous constructs to express CD24 and one or more of CR1/CD35, CD47, CD55, CD46, CD59 within a short list of immune evasion genes to express (e.g., a list of 13 polypeptides as recited in claim 63xvi) [0009, 0026, 0038, 0043, 0046, 0048, 0198, claims 3, 22], an ordinarily skilled artisan at the time of filing the instant application would have been motivated to express immune evasion genes comprising CR1/CD35, CD24, CD47, CD55, CD46, and CD59 within a limited number of options as taught by Schrepfer.
Regarding claims 10-11, Schrepfer teaches introducing exogenous constructs via a viral vector, such as a lentiviral vector [0209, 0215] and to introduce the exogenous constructs into a safe harbor locus which allows safe expression of a transgene or an exogenous gene, such as a PPP1R12C (AKA AAVS1) gene [0101, 0186, 0199].
However, Schrepfer does not teach wherein introducing exogenous constructs is preformed using an adeno-associated virus (AAV) construct, nor wherein the AAV construct is a modified AAVS construct that specifically targets a site of endogenous AAV integration located in an intronic region of PPPR12C.
However, Oceguera-Yanez teaches that the AAVS1 locus lies within the first intron of the constitutively expressed PPP1R12C gene [column 3 ¶ 3]. Oceguera-Yanez also teaches a method outlining the specific delivery of transgenic elements to the AAVS1 safe-harbor locus in human induced pluripotent stem cells (iPSCs), stimulated by a CRISPR/Cas9 nuclease system [column 3 ¶ 3]. Oceguera-Yanez also teaches using an AAV construct (e.g., donor vector) which is a modified AAVS construct that targets the endogenous AAVS1 locus/ the site of endogenous AAV integration located in an intronic region of PPP1R12C within iPSCs [column 4 ¶ 3-4, Table 1, Figure 2]. Oceguera-Yanez further teaches that using CRISPR/Cas9 nuclease technologies to introduce transgenes into pre-defined loci overcomes random position effects associated with viral or transposon vectors, and that AAVS1 is an exemplary locus within the PPP1R12C gene that permits robust expression of CAG promoter-driven transgenes [abstract]. Oceguera-Yanez also teaches that gene targeting controls transgene copy number such that reporter expression patterns are reproducible and scalable by ~2-fold, and that gene expression is maintained during long-term human iPSC culture and in vitro differentiation along multiple lineages [abstract].
Therefore, given the teachings of Oceguera-Yanez of a modified AAVS construct that targets the AAVS1 locus, and that targeting the AAVS1 locus overcomes random position effects, permits robust expression of transgenes that is maintained during long-term stem cell culture and along multiple differentiation lineages, an ordinarily skilled artisan at the time of filing the instant application would have been motivated to introduce a transgene into a stem cell using a modified AAVS construct that targets the AAVS1 locus within intron 1 of the endogenous PPP1R12C gene of the stem cell to achieve robust transgene expression during long-term culture and/or during differentiation of the stem cell to various lineages.
Regarding claim 14, Schrepfer teaches wherein the immune evasion genes further comprise HLA-E heavy chain [0006, 0138], but does not teach that the HLA-E heavy chain is comprised within an HLA-E single chain trimer.
However, Gornalusse teaches that disruption of the Beta-2 microglobulin (B2M) gene eliminates surface expression of all HLA class I molecules, but leaves the cells vulnerable to lysis by natural killer (NK) cells (e.g., a “missing self” response) [abstract]. Gornalusse further teaches that the “missing self” response can be prevented by forced expression of minimally polymorphic HLA-E molecules, including HLA-E single-chain trimers, in pluripotent stem cells (PSCs) such that the HLA-engineered PSCs and their differentiated derivatives are not recognized as allogeneic by CD8+ T cells, do not bind anti-HLA antibodies, and are resistant to NK-mediated lysis [abstract]. Gornalusse also teaches that single-chain HLA-E molecules prevent the NK-mediated lysis of B2M-/- cells without stimulating allogeneic T cells, addressing a major problem in the creation of universal donor cells for regenerative medicine application [column 2 ¶ 2]. Gornalusse additionally teaches that HLA-E forms a heterodimer with a B2M subunit and so it is not expressed on the surface of B2M-/- cells, but that B2M-/- cells could be engineered to express HLA-E as a single-chain protein fused to B2M, and thereby create cells that express HLA-E as their only surface HLA class I molecule [column 1 ¶ 2- column 2 ¶ 2, column 4 ¶ 1-2].
Therefore, given the teachings of Gornalusse that HLA-E expression overcomes the missing-self response associated with disruption of B2M expression, and the teaching that the HLA-E single-chain trimer overcomes the lack of surface expression of HLA-E in B2M-/- cells, an ordinarily skilled artisan at the time of filing the instant application would have been motivated to express an HLA-E single-chain trimer in a stem cell modified to reduce expression of HLA-I by abrogating expression of B2M to overcome the missing-self response and protect the cells from NK-mediated lysis in allogenic transplantation applications.
Given the motivation taught by Schrepfer to express immune evasion genes comprising CR1/CD35, CD24, CD47, CD55, CD46, and CD59 within a limited number of options; the motivation taught by Oceguera-Yanez to introduce a transgene into a stem cell using a modified AAVS construct that targets the AAVS1 locus within intron 1 of the endogenous PPP1R12C gene of the stem cell to achieve robust transgene expression during long-term culture and/or during differentiation of the stem cell to various lineages; and the motivation taught by Gornalusse to express an HLA-E single-chain trimer in a stem cell modified to reduce expression of HLA-I by abrogating expression of B2M to overcome the missing-self response and protect the cells from NK-mediated lysis in allogenic transplantation applications; it would have been prima facie obvious to an ordinarily skilled artisan at the time of filing the instant application to modify the method and cells of Schrepfer to include introducing exogenous constructs to express CR1/CD35, CD24, CD47, CD55, CD46, CD59, and HLA-E single chain trimer using a modified AAVS construct that targets a site of endogenous AAV integration located in an intronic region of PPPR12C with a reasonable expectation of success.
Conclusion
No claim is allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Dr. KATIE L PENNINGTON whose telephone number is (703)756-4622. The examiner can normally be reached M-Th 8:30 am - 5:30 pm, Friday 8:30 am - 12:30 pm CT.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Maria G. Leavitt can be reached on (571) 272-1085. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
DR. KATIE L. PENNINGTON
Examiner
Art Unit 1634
/KATIE L PENNINGTON/Examiner, Art Unit 1634
/MARIA G LEAVITT/Supervisory Patent Examiner, Art Unit 1634