DETAILED ACTION
Applicant’s amendment and response received on 3/31/26 has been entered. Claims 65 and 68 have been canceled. Claims 60-64, 66-67, and 69-81 are currently pending and under examination. The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . An action on the merits follows.
Claim Rejections - 35 USC § 112
The rejection of claims 60-81 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or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention, is withdrawn in view of applicant’s amendments to the claims and the cancelation of claims 65 and 68.
The rejection of claim 68 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112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement, is withdrawn in view of the cancellation of claim 68.
The rejection of claims 77-81 under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, for scope of enablement, is maintained. Applicant’s amendments to the claims and arguments have been fully considered but have not been found persuasive in overcoming the rejection for reasons of record as discussed in detail below.
The applicant argues that the specification provides the requisite disclosure for enabling the invention of claim 77. The applicant points out that the specific discloses specific combinations of transcription factors, vectors such as lentiviral vectors, and culture conditions including the use of cytokines for differentiation and reprogramming, and further argues that vector-mediated expression of transcription factors were standard approaches. The applicant also argues that the working examples show a precise combination of transcription factors, ETS1, TBET, NFIL3 and EOMES which are required to induce NK-cell characteristics, and can reprogram human embryonic fibroblasts towards the NK cell lineage. The applicant states that the specification further discloses that this technique can be applied to primary mammalian cell types other than fibroblasts and that the skilled artisan would understand that applying this methodology to other cell types involves only routine adaptation without undue experimentation. Finally, the applicant argues in regards to claim 81 that CD56-positive NK cells were well-established in the art as being useful for tumor cell killing.
In response, the Office has analyzed the specification in direct accordance to the factors outlined in In re Wands, namely 1) the nature of the invention, 2) the state of the prior art, 3) the predictability of the art, 4) the amount of direction or guidance present, and 5) the presence or absence of working examples, and presented detailed scientific reasons supported by publications from the prior art for the finding of a lack of enablement for the scope of the instant methods. The rejection of record set forth the following scope of enablement: the specification, while being enabling for 1) a method of inducing human embryonic fibroblasts to differentiate into CD34+ cells comprising transduction of the human embryonic fibroblasts in vitro with four lentiviral vector encoding one of the four different human transcription factors ETS1, TBET, NFIL3 and EOMES followed by culture of the cells for at least 6 days up to at least 12 days and 2) a method of inducing human embryonic fibroblasts to differentiate into CD56+ NK cells comprising transduction of the human embryonic fibroblasts in vitro with a lentiviral vector encoding the four different human transcription factors ETS1, TBET, NFIL3 and EOMES followed by culture in NK cell differentiation and activation media comprising at least IL-7, SCF, IL-3, IL-15, and FLT3L for at least 6 days up to at least 12 days, does not reasonably provide enablement for inducing or reprogramming any type of germ cell or somatic cell to generate a CD34+ cell or a CD56+ NK cell or any type of progenitor cell by expressing three or four of the transcription factors ETS1, TBET, NFIL3 and EOMES, or for treating any cancer by administering any construct or vector encoding three or four of the transcription factors ETS1, TBET, NFIL3 and EOMES in vivo in a subject.
Applicant’s argument that the guidance provided in the specification and the working examples are sufficient to enable the full scope of the claims as written because the method disclosed in the working examples can be applied to other starting cells types with no more than routine adaptation without undue experimentation is not agreed. The claims as amended remain broadly drawn to methods of reprogramming of inducing a cell into a natural killer cell or progenitor cell comprising transducing the cell with a construct or vector comprising at least one polynucleotide(s) encoding at least three of the transcription factors ETS1, TBET, NFIL3 and EOMES, and culturing the cells in media to obtain reprogrammed cells, or a method of treating cancer in a subject by administering a construct or vector comprising at least one polynucleotide(s) encoding at least three of the transcription factors ETS1, TBET, NFIL3 and EOMES. Claims 77-80 read broadly on the differentiation or transdifferentiation of any cell, such as a germ cell, any kind of stem or progenitor cell, or any kind of differentiated cell into either a progenitor cell or a natural killer cell. Note that claim 77 does not identify the progenitor cell as a progenitor cell or an NK cell, but rather reads broadly on any kind of progenitor cell such as a liver progenitor cell, a muscle progenitor cell, a kidney progenitor cell etc. The specification provides a general disclosure of the method in broad terms which focus on the use of vectors encoding three or four of the transcription factors ETS1, TBET, NFIL3 and EOMES to induce or reprogram a cell which may be any of a large number of discloses cell types including stem cell, progenitor cell, mature differentiated cells, and terminally differentiated cells. The specification also generally discloses the administration of a vector or construct encoding the three or four transcription factors to a subject to treat a variety of cancers.
Contrary to the bread of the claims and the generic nature of the disclosure in the specification, the working examples provide only two specific examples of reprogramming/induction. The working examples teach the induction of human embryonic fibroblasts to differentiate into CD34+ cells comprising transduction of the human embryonic fibroblasts in vitro with four lentiviral vector encoding one of the four different human transcription factors ETS1, TBET, NFIL3 and EOMES followed by culture of the cells for at least 6 days up to at least 12 days, and further a method of inducing human embryonic fibroblasts to differentiate into CD56+ NK cells comprising transduction of the human embryonic fibroblasts in vitro with four lentiviral vector encoding one of the four different human transcription factors ETS1, TBET, NFIL3 and EOMES followed by culture in NK cell differentiation and activation media comprising at least IL-7, SCF, IL-3, IL-15, and FLT3L for at least 6 days up to at least 12 days. The working examples demonstrate that they were able to produce a small number of CD34+ cells from human embryonic fibroblasts transduced with four separate vector encoding individually all four of the transcription factors ETS1, TBET, NFIL3 and EOMES after 6 days of culture post-transduction. The CD34+ cells are not further characterized such that it is unclear what type of progenitor cell was produced using this method. In a separate example, human embryonic fibroblasts transduced with four separate vector encoding individually all four of the transcription factors ETS1, TBET, NFIL3 and EOMES were cultured for 6 days post-transduction in the presence of NK cell differentiation and activation media comprising at least IL-7, SCF, IL-3, IL-15, and FLT3L resulting in the generation of a small number of CD56+ NK cell like cells. It is noted that these cells were not further characterized or tested for any NK cell functionality. The working examples also include a prophetic example which simply states that a variety of cancer can be treated by cells produced by the disclosed methods. Note in this case that this prophetic example does not teach to treat cancer by administering the transcription factors in vivo. Thus, aside from two specific examples for inducing/reprogramming human embryonic fibroblasts into either CD34+ cells or CD56+ cells, the working examples do not demonstrate or provide any specific guidance for inducing/reprogramming any cell other than an embryonic fibroblast cell into any kind of progenitor cell or NK cell. Further, the working examples clearly show that the post transduction culture conditions, particular the presence of different cytokines in the culture media substantially affects the cells produced where culture of human embryonic fibroblasts for 6 days post-transduction with the four transcription factors ETS1, TBET, NFIL3 and EOMES in basic culture media produced a small number of CD34+ cells, whereas culture of the same cells post-transduction for 6 days in the presence of NK cell differentiation and activation media comprising at least IL-7, SCF, IL-3, IL-15, and FLT3L resulting in the generation of a small number of CD56+ NK cell like cells. Thus, the culture media and presence of cytokines clearly play a key role in differentiation of the embryonic fibroblasts post-transduction into different cell types. It is also noted that these example used all four of the transcription factors. The specification does not provide sufficient guidance for using any three of the four factors in any starting cell population to induce differentiation or reprogramming into any other cell type.
The rejection of record also pointed out that at the time of filing, the four transcription factors ETS1, TBET, NFIL3 and EOMES were known to be important mediators of NK cell differentiation and maturation. Male et al., for examples, teaches the transduction of E4pb4 -/- common lymphoid precursor/stem (CLP) cells with a retroviral expression vector pMSCV encoding E4bp4 (NIFL3) under transcriptional control of the MSCV promoter which resulted in the development of NK cells (Male et al. (2014) J. Exp. Med., Vol. 211(4), 635-642, page 638). Male et al. teaches that the effects of E4bp4 on NK development were only effective in CLP cells and not in cells at a later stage of lymphoid or NK cell development (Male et al., page 638). Male et al. further generated a number of additional retroviral expression vectors encoding transcription factors, including EOMES, T-BET, Id2, Gata3, and ETS1, and tested them in E4pb4 -/- common lymphoid precursor (CLP) cells and in lineage depleted bone marrow cells, demonstrating that EOMES, T-BET, Id2, and ETS1 were each individually effective in rescuing NK cell development measured by expression of the NK1.1 marker protein, which Male et al. concludes show that they act downstream of E4bp4 in the hierarchy of NK cell development and contribute to NK cell development (Male et al., page 639 and Figure 4). It is also noted that Male et al. teaches in vitro development involved transducing the CLIP or lin- bone marrow cells with the retroviral vector encoding the transcriptional factor followed by culture in media comprising cytokines such as IL-7 and SCF (Male et al., page 641). Thus, while Male et al. teaches the importance of the expression of at least 4 transcription factors, E4pb4/NFIL3, EOMES, T-BET, and ETS1 for NK cell development, Male et al. shows that NK cell development required the expression of the transcription factors in specific progenitor cells, either CLIP cells, or lineage-negative bone marrow cells (lin-CD34+), and further required culture in media with the cytokines IL-7 and SCF. Neither Male et al. nor the prior art at the time of filing as a whole taught that any three of all of these four transcription factors was capable of inducing any stem or progenitor cell to differentiate into a CD34+ cell or an NK cell, or of reprogramming any differentiated cell into a CD34+ cell or an NK cell. Further at the time of filing, the differentiation or transdifferentiation of one cell type into another was considered unpredictable. Grath et al., in a review of cellular reprogramming, teaches that the main challenge when inducing transdifferentiation is choosing what transcription factors (TFs) to overexpress, and that many studies use a guess-and-check method, where TFs are chosen based on logical conclusions, such as the use of TFs that are active during the development of a cell type or drive the differentiation of stem cells into a specific cell type are often investigated first (Grath et al. (2019) J. Biol. Engineer., Vol. 13, 1-15, see page 3). It is further noted that the prior art is silent as to the use of any of these transcription factors for direct in vivo delivery to a subject for the treatment of any cancer. As such, the prior art at the time of filing taught the unpredictability of using transcription factors for reprogramming cells, requiring a guess-and-check approach in order to establish the effects of any one or more transcription factors on a cells ability to differentiate or be reprogrammed into another type of cell. The applicant has not addressed the publications from the prior art cited above, nor addressed the issues raised other than to state that use of any three of the four transcription factors claimed in any cell to generate any other type of cell would require no more than routine adaptation of their method. The state of the prior art as supported by Male et al. and Grath et al. above refutes this argument.
Therefore, it is maintained that in view of the high level of unpredictability in the prior art at the time of filing with regards to reprogramming/transdifferentiation using transcription factors, the general nature of the disclosure which broadly discloses the invention, the limitation of the working examples to two specific methods for reprogramming human embryonic fibroblasts into two specific cell types, and the breadth of the claims, it would have required undue experimentation to practice the scope of the methods as claimed.
Claim Rejections - 35 USC § 101
The rejection of claims 60-64 under 35 U.S.C. 101 because the claimed invention is directed to is directed to a judicial exception which is a product of nature without significantly more is withdrawn in view of applicant’s amendments to the claims which are now drawn to a construct or vector comprising polynucleotide encoding at least three different transcription factors selected from the group consisting of: ETS1, TBET, NFIL3 and EOMES.
Claim Rejections - 35 USC § 103
The rejection of pending claims 60-64, 66-67, and 71-80 under 35 U.S.C. 103 as being unpatentable over Male et al. (2014) J. Exp. Med., Vol. 211(4), 635-642, in view of Zhang et al. (2018) Eur. J. Immunol., Vol. 48, 738-750, Renoux et al. (2015) Immunity, Vol. 43, 394-407, Uniprot Accession Number Q6FG54_HUMAN (19-JUL-2004), Uniprot Accession Number Q9UL17 TBX21_Human (5-1-2000), Uniprot Accession Number D91VD5_HUMAN (5-OCT-2010), EP3258268-A1 (20-DEC-2017), hereafter referred to as Luking et al., KR2012061005-A (2012), hereafter referred to as Im et al., US Patent No. 6,812,339 (2004), hereafter referred to as Venter et al., WO 2002/28999 (2002), hereafter referred to as Beazer-Barclay, Hlavety et al. (2005) J. Virol., Vol. 341, 1-11, Zhang et al. (2014) Curr. Gene Ther., Vol. 14,10-23, hereafter referred to as Zhang 2014, and Fux et al. (2004) Biotech. & Bioengineer., Vol. 86(2), 174-187, is maintained. Note that claim 65 has been canceled. Applicant’s amendments to the claims and arguments have been fully considered but have not been found persuasive in overcoming the rejection for reasons of record as discussed in detail below.
The applicant argues that the scope of enablement rejection states that at the time of filing, the differentiation or transdifferentiation of one cell type into another was considered unpredictable and that therefore the position set forth in the enablement rejection is inconsistent with the obviousness rejection. The applicant further argues that significant experimentation was required on the part of applicant to identify ETS1, NFIL3, EOMES, and TBET capable of expand NCR1-positive colonies from transduced human embryonic fibroblasts. The applicant also argues that Male only tested ETS1, TBET, NFIL3 and EOMES separately using separate vectors and does not teach or suggest a single construct or vector encoding at least three of ETS1, TBET, NFIL3 and EOMES. In addition, the applicant argues that Male identifies 6 candidate transcription factors involved in NK cell development and that none of the references provide the requisite reasoning for selecting the specific combination of at least three of ETS1, TBET, NFIL3 and EOMES. According to applicant, Male et al. teaches away from this combination strategy by teaching that NFIL3 acts downstream of other factors and that ETS1 produced only a modest rescue of NK lineage compared to other factors. The applicant also argues that Male et al. only teaches differentiation of CLP or LMPP cells that are already committed to the lymphoid lineage and does not teach reprogramming differentiated cell such as fibroblasts. The applicant also argues that Zhang et al. and Renoux et al. offer at best only general background related to NK cell development and do not teach or provide motivation for combining transcription factors in a single vector for reprogramming. The applicant further states that the remaining references either are limited to provision of particular sequences, or are drawn to vector components or vectors which do not encode any of the claimed transcription factors and that these teachings fail to provide any motivation to make the claimed vector. Finally, the applicant argues that improper hindsight was used in the rejection of record.
In response to applicant's arguments against the references individually, it is noted that one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Further, the test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981). Obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007). Finally, in response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971).
In regards to the instant rejection, note that claims 60-64, 66-67, and 69-73 are product claims to a construct or vector encoding at least three transcription factors selected from ETS1, TBET, NFIL3 and EOMES. Claims 74-76 are also product claims drawn to a cell comprising the construct or vector. Claims 77-80 are method claims drawn to a method of in vitro cell reprogramming and claim 81 is a method of treating cancer comprising administering the construct or vector. Applicant’s arguments regarding the predictability or lack thereof of methods of differentiating or reprogramming cells does not apply directly to these product claims as they are simply products, not methods. Further, it is noted that the enablement rejection referred to by the applicant is a scope of enablement rejection applied only to claims 77-81. Also note that claim 81 is not included in this rejection. It is not agreed that there is a contradiction between the identified enabled scope and the instant rejection based on obviousness. The finding of obviousness based primarily on the teachings of Male et al. and Zhang et al. were limited to a finding of obviousness in transducing mouse or human CD34+ CLP cells or lin-CD34+ bone marrow stem cells in vitro with retroviral vectors encoding E4pb4/NFIL3, EOMES, T-BET, and ETS1, or E4pb4/NFIL3, EOMES, T-BET, ETS1, ID2, and Gata3 in order to induce the differentiation of these cells into CD56+ NK cells with a reasonable expectation of success. The identified enabled scope in the 112 rejection was similar to this subject matter. The issues regarding enablement were based on the scope of claims 77-81 which are much broader than the identified scope or the teachings of Male et al. and included the reprogramming or induction or any stem or differentiated cell into an NK or NK-like cell using any 3 of the four claimed transcription factors. The unpredictability in the art referred discussed in the enablement rejection was directed to this breadth. The rejection even cited Male et al. as evidence of what was currently known in the art at the time of filing with specific regards to the claimed transcription factors and generation of NK cells. Thus, there is no inconsistency between the enablement rejection and the instant rejection.
Turning to teachings of Male et al., Male et al. was cited for teaching that ETS1, T-BET, and E4bp4 (NIFL3) are all important transcription factors which are required for NK cell committed NK progenitor development, and the generation of NK1.1 positive NK cells (Male et al., pages 635, and pages 638-639). In particular, Male et al. teaches that E4bp4 is particularly important early in NK cell development, and that EOMES, Id2, IRF2, and MF are important in acting later in NK development and maturation (Male et al., page 635). Male et al. further teaches the transduction of E4pb4 -/- common lymphoid precursor/stem (CLP) cells with a retroviral expression vector pMSCV encoding E4bp4 (NIFL3) under transcriptional control of the MSCV promoter which resulted in the development of NK cells (Male et al., page 638). Male et al. teaches that the effects of E4bp4 on NK development were only effective in CLP cells and not in cells at a later stage of lymphoid or NK cell development (Male et al., page 638). Male et al. further generated a number of additional retroviral expression vectors encoding transcription factors, including EOMES, T-BET, Id2, Gata3, and ETS1, and tested them in E4pb4 -/- common lymphoid precursor (CLP) cells and in lineage depleted bone marrow cells, demonstrating that EOMES, T-BET, Id2, and ETS1 were each individually effective in rescuing NK cell development measured by expression of the NK1.1 marker protein, which Male et al. concludes show that they act downstream of E4bp4 in the hierarchy of NK cell development and contribute to NK cell development (Male et al., page 639 and Figure 4). It is also noted that Male et al. teaches in vitro development involved transducing the CLIP or lin- bone marrow cells with the retroviral vector encoding the transcriptional factor followed by culture in media comprises cytokines such as IL-7 and SCF (Male et al., page 641). Thus, Male et al. teaches the importance of the expression of at least 4 transcription factors, E4pb4/NFIL3, EOMES, T-BET, and ETS1, and two additional transcription factors ID2, and Gata3, in NK cell development from lymphoid stem cells such as CLP cells or lineage depleted bone marrow cells, thus providing motivation to express all four of E4pb4/NFIL3, EOMES, T-BET, and ETS1 in CLP cells or lineage depleted bone marrow cells in order to induce development of NK cells. Applicant’s argument that because Male et al. shows that E4pb4 acts upstream of EOMS, T-BET, and ETS1 this teaches away from combining E4pg4 with the other downstream transcription factors is not persuasive since Male et al. shows that each of these transcription factor is in fact important and active in NK cell development form lymphoid stem cell. Further as lineage depleted bone marrow cells are not a homogenous cell type and include various stem/precursor cells including CLP cells and precursor cells at a later stage in NK cell development than CLP cells, the skilled artisan would have had ample motivation to combine all of the transcription factors which Male et al. showed were active in CLP cells or later precursor cells in order to maximize the induction of development of NK cells.
In regards to Zhang et al. and Renoux et al., these secondary references were included to provide a reasonable expectation that following the teachings of Male using human cells would be successful. Male et al. tested the effects of the expression of these transcription factors on mouse cells; however, Zhang et al. teaches that mouse and human cells follow a similar path of NK cell development from CLIP cells (referred to as CILP cells in Zhang), including the importance of expression of T-BET and EOMES for later stage mature NK cell development (Zhang et al., page 743, Figure 3). In particular, Zhang et al. teaches that T-BET and EOMES cooperate to promote NK cell maturation and homeostasis (Zhang et al., page 745). Renoux et al. further supplements Male et al. by teaching that CLP cells and lin- bone marrow cells express CD34 (Renoux et al., graphical abstract). Renoux et al. further demonstrates that human lin-CD34+ bone marrow develop in vivo in NOD/SCID mice into mature CD56+ NK cells and that such mature CD56+ NK cells express both T-BET and EOMES (Renoux et al., pages 397, 402-403, and Figure 4). Thus, in view of the of teachings of Male as to the importance of all four of E4pb4/NFIL3, EOMES, T-BET, and ETS1 in NK cell development from CLP cells, the further teachings of Male et al. for the importance of additional transcriptional factors in NK cell development such as ID-2 and Gata3, the teachings of Zhang et al. that mouse and human NK development are similar and that T-BET and EOMES cooperate in NK cell development, particularly the development of mature NK cells in both mouse and humans, the teachings of Male et al. that retroviral vectors encoding transcription factors including E4pb4/NFIL3, EOMES, T-BET, and ETS1 can be used to transduce CLP cells or lineage depleted bone marrow cells in order to induce development of NK cells in vitro in the presence of cytokines, and the teachings of Renoux et al. that human lin- bone marrow cells and CLP cells are CD34+ and develop into NK cells that express CD56, it would have been prima facie obvious to the skilled artisan at the time of filing to transduce mouse or human CD34+ CLP cells or lin-CD34+ bone marrow stem cells in vitro with retroviral vectors encoding E4pb4/NFIL3, EOMES, T-BET, and ETS1, or E4pb4/NFIL3, EOMES, T-BET, ETS1, ID2, and Gata3 in order to induce the differentiation of these cells into CD56+ NK cells with a reasonable expectation of success.
Uniprot Accession Number Q6FG54_HUMAN (19-JUL-2004), Uniprot Accession Number Q9UL17 TBX21_Human (5-1-2000), Uniprot Accession Number D91VD5_HUMAN (5-OCT-2010), EP3258268-A1 (20-DEC-2017), hereafter referred to as Luking et al., KR2012061005-A (2012), hereafter referred to as Im et al., US Patent No. 6,812,339 (2004), hereafter referred to as Venter et al., and WO 2002/28999 (2002), hereafter referred to as Beazer-Barclay, were cited to supplement Male et al. by teaching the well known amino acid sequences for ETS1, T-BET, E4bp4/NFIL3, and EOMES which are 100% identical to SEQ ID NOS: 1-4 respectively, and polynucleotide sequences encoding these amino acid sequences which are greater than 95% identical to SEQ ID NOS 22-25 respectively. These references were not relied upon to provide motivation to use these sequences to induce differentiation of a stem cell such as a CLP cell or lineage depleted bone marrow cells into NK cells using the claimed transcription factors as the teaching for using these specific transcription factors to induce NK cell differentiation of these particular stem cells was already provided by Male et al. As noted in the rejection of record, based on these well known sequences, it would have been prima facie obvious to the skilled artisan at the time of filing to transduce mouse or human CD34+ CLP cells or lin-CD34+ bone marrow stem cells in vitro with retroviral vectors encoding ETS1, T-BET, E4bp4/NFIL3, and EOMES as taught by Male et al. in view of Zhang et al. and Renoux et al. with the amino acid sequences of SEQ ID NO:1-4 respectively, and/or where the polynucleotide sequences for each transcription factor are selected from the polynucleotide sequences taught by Im et al., Venter et al., Beazer-Barclay et al., and Luking et al. respectively, in order to induce the differentiation of these cells into CD56+ NK cells with a reasonable expectation of success.
Turning to the use of the WPRE in a vector encoding a transcription factor, or the use of Semliki virus replicons as the vector for expression a transcription factor, the rejection of record noted that while Male et al. teaches to express the transcription factors E4pb4/NFIL3, EOMES, T-BET, and ETS1 in a retroviral vector, Male et al. does not teach the use of a PRE in the vector, or the use of a naked alphavirus replicon(s) to express the transcription factors, or to express the transcription factors using a single vector encoding three or four of the transcription factors. Hvalaty et al. was cited to supplement Male et al. by teaching that the inclusion of a PRE such as the woodchuck post transcriptional regulatory element (WPRE) in a retroviral vector substantially enhanced transgene expression in transduced cells (Hvalaty et al., pages 1 and 8). Thus, based on the motivation provided by Hvalaty et al. to include a PRE such as WPRE in a retroviral vector to enhance transgene expression in transduced cells, it would have been prima facie obvious to the skilled artisan at the time of filing to include an WPRE in the retroviral vectors encoding the transcription factors E4pb4/NFIL3, EOMES, T-BET, and ETS1 according to Male in view of Zhang et al. and Renoux et al. with a reasonable expectation of success. Zhang 2014 was cited for teaching that in contrast to integrating viral vectors such as retroviral vectors which can risk insertional mutagenesis in cells, autonomously replicating genetic elements such as alphavirus RNA replicons, in particular Semliki virus replicons, are non-integrating autonomous replicating vectors which are maintained episomally and can express therapeutic sequences in target cell and tissues (Zhang 2014, pages 10 and 12). Zhang 2014 also teaches to deliver naked SFV RNA replicons (Zhang 2014, page 12). Thus, based on the advantages to using a Semliki virus replicon, particularly a naked Semliki virus replicon over a retroviral vector to express a desired sequence in a target cell as taught by Zhang et al., it would have been prima facie obvious to the skilled artisan at the time of filing to utilize the naked Semliki virus replicon to encode and express the E4pb4/NFIL3, EOMES, T-BET, and ETS1 transcription factors according to Male in view of Zhang et al. and Renoux et al. with a reasonable expectation of success.
Turning to the use of a single vector, while Male et al. teaches individual retroviral vectors encoding each of E4pb4/NFIL3, EOMES, T-BET, and ETS1, other vectors for expressing more than one gene of interest in cells were available at the time of filing. Fux et al. teaches the a multi-cistronic expression vector which can express three or four different genes from a single promoter (Fux et al., page 179). Fux et al. teaches that the pTRIDENT plasmid can be used to transfect cells or that the expression cassette of the pTRIDENT vector can be inserted into a lentiviral vector for cell transduction (Fux et al., page 180-181 and Figure 4, and pages 185-186 and Figure 7). In experiments using a tri-cistronic version of the plasmid or lentivirus, Fux et al. shows the comparable expression of all three encoded genes in cells (Fux et al., Figures 4 and 7). Fux et al. teaches that the advantages of the multicistronic vector are simultaneous high-level expression of multiple genes in a single cell (Fux et al., page 174). Fux et al. is not required to teach or suggest that the single vector encode the 3 or 4 transcription factors as claimed. Fux et al. was cited for providing motivation to use a single vector to encode multiple genes instead of separate vectors. Thus, based on the advantages to using a single multicistronic cells to express multiple genes in a single cell as taught by Fux et al., it is maintained that it would have been prima facie obvious to the skilled artisan at the time of filing to utilize the a multicistronic plasmid or lentiviral vector as taught by Fux et al. to encode and express the E4pb4/NFIL3, EOMES, T-BET, and ETS1 transcription factors according to Male in view of Zhang et al. and Renoux et al. with a reasonable expectation of success. Furthermore, as Fux et al. shows comparable expression of the genes from each cistron present in the multicistronic vector, it is maintained that it would have been prima facie obvious to the skilled artisan at the time of filing to include the four polynucleotide sequences for E4pb4/NFIL3, EOMES, T-BET, and ETS1 in any order in the multicistronic vector taught by Fux et al. with a reasonable expectation that all four transgenes would be capable of being expressed from the vector in cells.
Finally, in regards to applicant’s argument that Male et al. only teaches differentiation of CLP or LMPP cells that are already committed to the lymphoid lineage and does not teach reprogramming differentiated cell such as fibroblasts. It is noted that the claims are not limited to the methods of reprogramming differentiated cells such as fibroblasts. Method claims 77-79 are broadly drawn to reprogramming or inducing a cell into a natural killer cell or progenitor cell (claim 77). Claim 79 identifies the starting cell as a stem cell or differentiated cell. Claim 80 recited that the reprogrammed cell is NCR1+, CD34+, or CD56+. Thus, the broadest claim, claim 77 does not limit either the starting cell or the ending cell to any particular cell type, despite the preamble reciting that the method generates a natural killer cell or progenitor cell. The narrowest dependent claims, 79 and 80, read on inducing differentiation/reprogramming of any stem cell, and on generating a cell with specific lymphoid stem cell marker or NK marker expression. Thus, applicant’s argument regarding a lack of teaching in Male for reprogramming differentiated cells is effectively a argument based on limitations which are not present in the claims as written and therefore is not persuasive.
No claims are allowed.
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication from the examiner should be directed to Anne Marie S. Wehbé, Ph.D., whose telephone number is (571) 272-0737. If the examiner is not available, the examiner’s supervisor, Maria Leavitt, can be reached at (571) 272-1085. For all official communications, the technology center fax number is (571) 273-8300. Please note that all official communications and responses sent by fax must be directed to the technology center fax number. For informal, non-official communications only, the examiner’s direct fax number is (571) 273-0737. For any inquiry of a general nature, please call (571) 272-0547.
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. A.M.S. Wehbé
/ANNE MARIE S WEHBE/Primary Examiner, Art Unit 1634
Prosecution Insights