DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claims 1-3, 7, 10, 13-15, 18-20, 22, 23, 26, 31-33 are pending in the application.
Claims 32 and 33 are withdrawn from consideration. Claims 1-3, 7, 10, 13-15, 18-20, 22, 23, 26 and 31 are currently under examination.
This office action is in response to the amendment filed on 6/8/2026.
All previous rejection not reiterated in this office action are withdrawn.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
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, 7, 14 and 26 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ostertag (WO 2020/051374), in view of sequences have accession number JQ048536, JQ087288 and KF420799. This rejection has been rewritten to address the amendment.
Claim 1 is drawn to an HLA class Ineg cell population, wherein said cells are antigen presenting cells, and comprise a disruption in the HLA-A, HLA-B and HLA-C genes, produced by CRISPR/Cas9 mediated gene disruption targeting a consensus sequence SEQ ID NO: 1, do not have expressible HLA class-I protein, and further comprises an expression construct for an exogenous HLA class I gene from a human cancer patient.
Ostertag teaches a method for generating MHCI knockout cells comprising using guide RNA selective for HLA-A, HLA-B and HLA-C (paragraph [0226]). Ostertag teaches HLA-A, HLA-B and HLA-C is reduced or eliminated in allogeneic cells (paragraph [066]). Ostertag teaches that specifically guides were designed to target a conserved region occurring in all the three MHCI protein targets, but not in HLA-E, and the MHCI knockouts were verified by surface expression of said HLA I proteins (paragraph [066]). Ostertag teaches the modified cell encompasses antigen presenting cell (page 43, paragraph [0125], lines 1-4). Ostertag teaches the HLA-A, B and C knockout cells may further express a non-naturally occurring sequence comprising HLA-E transiently or stably (paragraph [0112] and paragraph [0127]), which meets the limitation of comprise an expression construct for an exogenous HLA class I gene.
The only difference between the invention of claim 1 and Ostertag’s MHCI knockout cells is that the consensus sequence is not SEQ ID NO: 1 as claimed, and HLA class I gene construct is obtained from a human cancer patient using locus specific primer pairs.
SEQ ID NO: 1 shares 100% sequence identity with JQ048536, JQ087288 and KF420799 (see attached alignment).
JQ048536 is from human MHC class I antigen (HLA-A) gene, JQ087288 is from HLA-B gene, and KF420799 is from HLA-C gene, so that they are consensus sequence shared between HLA-A, HLA-B and HLA-C.
It would have been obvious to an ordinary skilled in the art that SEQ ID NO:1 would be a good candidate for designing gRNA for CRISPR/Cas9 mediated disruption of all HLA class I gene, A, B and C because it is a consensus sequences shared by all three genes. Following the teaching from Ostertag, it would have been obvious to use this approach to design additional gRNA for producing HLA class I gene disruption. Substitute one consensus sequence with another to achieve a predictable result would have been within the capability of an ordinary skilled in the art. It would have been obvious to an ordinary skilled in the art that the HLA-E introduced into the modified immune cell would come from a patient, preferably the patient being treated for a disorder to reduce rejection because that’s the intended purpose of modifying said cells. Whether it is cloned by locus specific primer does not change the structure/sequence of the gene encoding HLA-E. Therefore, the claimed invention of claim 1 would have been prima facie obvious to an ordinary skilled in the art at the time the application was filed.
Regarding claim 7, it would have been obvious to an ordinary skilled in the art that treating cells comprising knockouts of HLA-A, B and C with cytokines IFNγ and/or TNFα would not produce HLA-A, B and C expression because the gene is disrupted.
Regarding claim 14, the method of which the expression is construct would not impart a structural difference between the prior art disclosed construct and the claimed construct. Ostertag teaches HLA-E comprises amino acids SEQ ID NO: 17066, and encoded by nucleic acid SEQ ID NO: 17067 (paragraph [[0122]). Ostertag teaches the modified cell may express HLA-E stably or transiently (paragraph [0127]). It would have been obvious to an ordinary skilled in the art that the nucleic acid sequence encoding HLA-E would have the same structure regardless whether it is assembled by Gibson assembly. Since Ostertag teaches the nucleic acid encoding HLA-E, absent evidence from the contrary, the claimed invention of claim 14 would have been obvious in view of combined teaching from Ostertag, and JQ048536, JQ087288 and KF420799.
Regarding claim 26, Ostertag teaches the T cell may be cultured in an activation supplement that comprises cytokines including IL2 and IL15 (paragraph [0311]).
Response to Arguments
Applicant states that Ostertag discloses at paragraph [0226] an approach using gene editing with guide RNAs selective for HLA-A, B and C, but not HLA-E, such that separate guide RNAs for HLA, B and C. Applicant argues that accession number JQ048536, JQ087288 and KF420799 merely teach the complete sequences of HLA-A, B and C genes, but no teaching for the use of sequences to produce a highly efficient consensus sequence which targets all three genes. Applicant submitted a declaration from Dr. Hiroki Torikai shows the efficacy of three different consensus sequences that were tested before selecting the consensus sequence in the instant claims. Applicant alleges the consensus sequence targeted by CRISPR/Cas9-mediated gene disruption is SEQ ID NO: 1, which has surprising efficacy at binding to HLA-A, C and C as compared to other consensus sequences. Applicant asserts that designing a highly efficient guide RNA that minimizes unintended mutations requires careful planning and strategic selection, which can be challenging. Applicant argues that Ostertag is directed to modifying T cells to be MHCI knockout, whereas the presently claimed cells are antigen presenting cells that very efficiently have disrupted expression of HLA-A, B and C genes. Applicant states these APC can present HLA polypeptide at the cell surface to product antigen specific immune effector cells, which differs from the cells taught by Ostertag.
The declaration under 37 CFR 1.132 filed 6/8/2026 is insufficient to overcome the rejection of claims 1, 7, 14 and 26 based upon Ostertag and the sequences of JQ048536, JQ087288 and KF420799 as set forth in the last Office action for reason discussed below.
Applicant’s arguments have been fully considered but deemed unpersuasive. Paragraph [0226] from Ostertag does not specifically states how many guide RNA is used to target HLA-A, B and C. However, paragraph [0066] from Ostertag teaches guides were designed to target a conserved region occurring in all the three MHCI protein targets (A, B and C), which meets the limitation of a consensus sequence shared between all three genes. The fact that multiple guides were used illustrates that it is routine practice in prior art to design multiple guides and screening for the most efficient guide RNA for CRISRP system to knockout a specific sequence (see Figure 29). As such, while the declaration teaches testing 3 different gRNAs for targeting different consensus sequences with SEQ ID NO: 1 showed high efficacy in gene editing, such practice would have been considered as optimization, rather than method of innovation. The examination acknowledges careful planning and strategic selection is required to design a gRNA targeting a specific sequence, it would have been routine process because there are commercially available software to design gRNA, and making a selection based on experimentation data would have been obvious as demonstrated by the teaching from Ostertag. Since the prior art teaches sequences encoding HLA-A, B and C (JQ048536, JQ087288 and KF420799), identifying consensus sequence from said sequences would simply involve an alignment of all sequences, which would have been routine experimentation at the time this application was filed. There would only be a finite number of consensus sequences between these sequences so that substituting one with another would have been optimization rather than method of innovation. With regard to the argument directed to antigen presenting cell, the rewritten rejection set forth above indicates that Ostertag’s teaching encompasses modified antigen presenting cells. Therefore, the above rejection is still considered proper and thus maintained.
Claim(s) 1-3, 7, 10, 13-15, 18, 19, 22-23, 26 and 31 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hong (Journal of Immunotherapy, 2017, Vol.40, no.6, pages 201-210), in view of JQ048536, JQ087288 and KF420799. This rejection has been rewritten to address the amendment.
Hong teaches generating HLA class I null cell line using multiplex CRISPR/Cas9 system by targeting exon 2 and 3 of HLA-A, HLA-B and HLA-C genes simultaneously. Hong teaches that artificial antigen presenting cells were generated by transfer of a single HLA class I allele and co-stimulatory molecules into HLA class I null cell line. Hong teaches artificial antigen presenting cells showed HLA-restricted antigen presentation following antigen processing and were successfully used for the efficient generation of tumor antigen specific cytotoxic T cells in vitro. Hong teaches the efficient editing of HLA genes may provide a basis for universal cellular therapies and transplantation (entire abstract). Hong further teaches transfer of a single HLA class I allele HLA-A and HLA-B into this HLA class null cell line (page 205, 2nd col., 1st paragraph).
However, Hong does not specifically teach what the consensus sequence they used to generate the HLA I null cell line. Hong does not teach whether the exogenous HLA class I gene is cloned from a human cancer patient using locus specific primer pairs.
SEQ ID NO: 1 shares 100% sequence identity with JQ048536, JQ087288 and KF420799 (see attached alignment).
JQ048536 is from human MHC class I antigen (HLA-A) gene, JQ087288 is from HLA-B gene, and KF420799 is from HLA-C gene, so that they are consensus sequence shared between HLA-A, HLA-B and HLA-C.
It would have been obvious to an ordinary skilled in the art that SEQ ID NO:1 would be a good candidate for designing gRNA for CRISPR/Cas9 mediated disruption of all HLA class I gene, A, B and C because it is a consensus sequences shared by all three genes. Substitute one consensus sequence with another to achieve a predictable result would have been within the capability of an ordinary skilled in the art. It would have been obvious to an ordinary skilled in the art for intended cancer cellular therapy, the APC would need have matched HLA class I to reduce GvH reaction to present tumor antigen. As such, the ordinary skilled in the art would be motivated to use an HLA class I gene from a cancer patient. The method used to clone the gene does not result in any structural/sequence difference between the HLA class I gene being cloned. Therefore, the claimed invention of claims 1 and 10 would have been prima facie obvious to an ordinary skilled in the art at the time the application was filed.
Regarding claim 2, the cell line taught by Hong meets the limitation of immortalized cell line.
Regarding claim 3, Hong teaches the immortalized cell line is 293 T cells (page 205, 2nd col., lines 1-3).
Regarding claim 7, it would have been obvious to an ordinary skilled in the art that treating cells comprising knockouts of HLA-A, B and C with cytokines IFNγ and/or TNFα would not produce HLA-A, B and C expression because the gene is disrupted.
Regarding claim 13, Hong teaches the modified APC showed HLA-restricted antigen presentation following antigen processing and were successfully used for the efficient generation of tumor antigen specific cytotoxic T cells in vitro. Whether the patient has been HLA typed does not change the structure of the class I HLA gene being introduced into the APC cell.
Regarding claim 14, it would have been obvious to an ordinary skilled in the art that the nucleic acid sequence encoding HLA-I would have the same structure regardless whether it is assembled by Gibson assembly. Since Hong teaches the lentiviral vectors that encoding nucleic acid encoding HLA class I allele, absent evidence from the contrary, the claimed invention of claim 14 would have been obvious in view of combined teaching from Hong, and JQ048536, JQ087288 and KF420799.
Regarding claims 15, 18 and 19, Hong teaches the modified APC showed HLA-restricted antigen presentation following antigen processing and were successfully used for the efficient generation of tumor antigen specific cytotoxic T cells in vitro. Hong teaches transduction of additional genes including CD80, CD32, CD83, 4-1BBL, CD54 and CD70 and stimulated the cells with MART-126-35 peptide (page 206, 2nd col., lines 1-6). Hong teaches it generated antigen specific CTL (Figure 5 and legend). It would have been obvious to an ordinary skilled the in the art that the AAPC cells that presents tumor antigen would be loaded with MART-1 and present it at the cell surface.
Regarding claims 22 and 23, Hong teaches the stimulated cells are co-cultured with purified T cells (page 203, 2nd col., 1st paragraph).
Regarding claim 26, Hong teaches culturing medium for generating antigen specific cytotoxic T cells comprises IL2 and IL15 (page 203, 1st col., last paragraph).
Regarding claim 31, since there is no definition for “candidate TCR,” the TCR that binds MART-1 in the effector T cells meets this limitation because the purified T cells would necessarily have a TCR that specially stimulate the CTL response for antigen specific T cells.
Claim(s) 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hong and JQ048536, JQ087288 and KF420799, as applied to claim 1 above, and further in view of Aubin (Molecular Biotechnology, 1994, Vol.1, pages 29-48).
The teaching from Hong has been discussed above. However, Hong does not teach the cells are cultured in the presence of polybrene.
Aubin teaches polybrene/DMSO assisted gene transfer is a simple and versatile transfection strategy capable of producing high numbers of stable transfects from adherent monolayer cultures with low quantities of exogeneous DNA, wherein polybrene favors uniform coating of target cells. Aubin teaches diverse cell types can be exposed to a wide range of polybrene concentrations without adverse effects (abstract). Aubin teaches optimized protocols for gene transfer in murine and human cells (abstract).
It would have been obvious to an ordinary skilled in the art to add polybrene into the culture medium for culturing engineered APC knockout taught by Hong because Aubin teaches polybrene assists gene transfer. The ordinary skilled in the art would be motivated to include polybrene because Aubin teaches polybrene is a simple and versatile transfection strategy capable of producing high numbers of stable transfectants for diverse cell types. Adding a compound into a cell culture for its predictable effect would have been prima facie obvious to an ordinary skilled in the art at the time the application was filed.
Response to Arguments
Applicant repeated arguments directed to the consensus sequence of SEQ ID NO:1. This argument has been addressed above.
Applicant further argues that Hong uses six gRNAs targeting HLA-A exon 2, HLA-A exon 3, HLA-B exon 2, HLA-C exon 2 and exon 3, which is a distinct method from the present method in which a single consensus sequence efficiently disrupts HLA-A, B and C genes. Applicant alleges that Hong does not teach the use of an exogenous HLA class I gene cloned from a human cancer using locus specific primer pairs to target and amplify a single distinctive region of a genome, whereas the present methods provide streamlined HLA class I cloning, stable expression in HLA-I negative HEK293T cells, and the production of lentivirus particles for identifying and validating tumor specific antigens for T cells. Applicant states that negative HLA stimulator cells produced by current method are non-adherent cells which cannot be used to produce lentivirus vector, whereas simultaneous production of HLA-I negative HEK293T cells expressing patient derived HLA and lentivirus vector can facilitate the process of identifying tumor associated antigens and their corresponding TCRs.
The above argument has been fully considered but deemed unpersuasive. Applicant is reminded that the claimed invention is directed to a product, an HLA class Ineg antigen presenting cell population, that also expresses a expression construct for an exogenous HLA class I gene cloned from a human cancer patient. Absent evidence from the contrary, the method by which the cell population is obtained, and/or the HLA class I gene being cloned, does not impart upon said cell or HLA class I gene a patentable distinction structurally from the cell population rendered obvious by the teaching from prior art (Hong). In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., the streamlined HLA class I cloning by locus specific primer pairs, and/or simultaneous production of HLA-I negative HEK293T cells) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993). Therefore, for reason discussed in previous rejection and set forth above, this rejection is still considered proper and thus maintained.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CELINE X QIAN whose telephone number is (571)272-0777. The examiner can normally be reached M-F (8-4:00).
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, Jennifer Dunston can be reached at 571-272-2916. 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.
/CELINE X QIAN/ Primary Examiner, Art Unit 1637
Prosecution Insights