DETAILED ACTION
Notice of Pre-AIA or AIA Status
1. The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Election/Restrictions
2. Applicant’s election without traverse of Group II, claims 6-22 in the reply filed on 27 April 2026 is acknowledged. Applicant has withdrawn claims 1-3 as they are drawn to the nonelected invention.
Claim Status
3. Claims 1-3 are withdrawn.
Claims 4-5 are canceled.
Claim 6 is amended.
Claims 6-22 are under consideration.
Priority
4. Acknowledgment is made of applicant's claim for foreign priority based on an application filed in the People’s Republic of China on 15 December 2022. It is noted, however, that applicant has not filed a certified copy of the CN202211619775.8 application as required by 37 CFR 1.55. Therefore, the effective filing date of the Instant Application is 09 October 2023.
Specification
5. 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.
Claim Objections
6. Claims 6-7, 9, 11-14, and 17-22 objected to because of the following informalities:
Regarding claim 6, the word “system” should be added after “two phrase” in line 2. Examiner also suggests adding the word “comprising” after “composition” in line 3 and deleting the subsequent phrase “, wherein the aqueous… composition comprises”.
Regarding claims 7 and 13-14, “a process of” should read “the process of”, the commas after “composition” and “two-phase system” should be changed to semicolons for consistency, the commas after “three-phase system” and “PBS solution” should be removed, and “the mixture” should be added after “allowing”.
Regarding claim 9, “an obtained infected plant tissue” should read “the obtained infected plant tissue” and “(EDTA)” should be removed. Examiner also suggests adding an actual infection step between the construction of the strain and the crushing/extraction steps.
Regarding claims 11-12, the “in” after “wherein” should be removed, “KH2PO4” and “K2HPO4” should have their numbers written in subscript for consistency with claim 1, and the commas before “and the K2HPO4” should be removed.
Regarding claims 17-22, “Agrobacterium” should be italicized for consistency with claim 9, “an obtained infected plant tissue” should read “the obtained infected plant tissue”, and “(EDTA)” should be removed.
Appropriate correction is required.
Claim Rejections - 35 USC § 103
7. 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.
8. 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.
9. Claims 6 and 11-12 is rejected under 35 U.S.C. 103 as being unpatentable over Xu (2005, J. Zhejiang Univ. SCI., 6B(11): 1087-1094) and Luechau (October 2011, Food and Bioproducts Processing, 89(40): 322-327).
Regarding claims 6 and 11-12, Xu teaches “This paper presents the evaluation of an aqueous two-phase system (ATPS) for extracting elastase produced by Bacillus sp. EL31410. The elastase and cell partition behavior in polyethylene glycol (PEG)/salt systems was investigated. The suitable system for elastase extraction was PEG/KH2PO4-K2HPO4” (Abstract), wherein they tested multiple PEG MWs, including PEG400 (Materials, ¶ 1; Figure 2). Xu further teaches “After separation and centrifugation, the cells readily entered into the bottom phase or precipitated at the interface according to the partition coefficient, especially in PEG/KH2PO4-K2HPO4” (Results and Discussion, ¶ 1), this separation and centrifugation reads on the “separating and purifying” recited in the claims. Xu does not teach using ATPS in the context of VLPs.
However, Luechau teaches purifying B19 VLPs made using insect cells (2.1 Materials) with ATPS using PEG and phosphate (2.5 ATPS experiments). Since Xu teaches that a large range of PEG MWs (including PEG400) worked, it would be predictable that PEG400 would at least be functional in Luechau’s system. Therefore, it would have been obvious to use the method of Xu with VLPs as it will be predictably functional, as taught by Luechau. The combination of familiar elements is likely to be obvious when it does no more than yield predictable results. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395 – 97 (2007) (see MPEP § 2143, A.). A rationale to support a conclusion that a claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would have yielded nothing more than predictable results to one of ordinary skill in the art. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395 (2007) (see MPEP §§ 2143, A. and 2143.02).
Xu further teaches “The optimal ATPS was 23.1% (w/w) PEG 2000 and 11.7% (w/w) KH2PO4-K2HPO4” (Abstract) and shows that the molecular weight of PEG used can also be adjusted for optimal elastase partitioning (Page 1090, ¶ 3), see Figure 2:
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Therefore it would be obvious that the PEG400 and KH2PO4-K2HPO4 mass fractions, as well as the PEG molecular weight would be result-effective variables that are routinely optimized. The mass fractions and PEG molecular weight used will affect the concentrations needed for phase separation as well as which layer the target molecules, in this case the VLPs, will separate into. For example, Luechau used 15.7% (w/w) PEG and 9.4% (w/w) phosphate where they saw that caused the B19 particles to distribute between both the top and bottom phases (2.5 ATPS experiments and 3.1 Process routes for the recovery of B19 particles from non-clarified cell disruptate). Additionally, Xu saw separation of elastase into the top phase of their system (1089, last ¶) whereas Luechau saw separation of the B19 particles into the bottom phase (Figure 2) in one system and into the interface (Figure 4) in others, thus illustrating the variation between systems depending on buffer concentrations, mass fractions, molecular weight, and interactions between the buffers used and the target molecule. It has long been settled to be no more than routine experimentation for one of ordinary skill in the art to discover an optimum value of a result effective variable. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum of workable ranges by routine experimentation." Application of Aller, 220 F.2d 454, 456, 105 USPQ 233, 235-236 (C.C.P.A. 1955). "No invention is involved in discovering optimum ranges of a process by routine experimentation." Id. at 458, 105 USPQ at 236-237. The "discovery of an optimum value of a result effective variable in a known process is ordinarily within the skill of the art." Application of Boesch, 617 F.2d 272, 276, 205 USPQ 215, 218-219 (C.C.P.A. 1980). Since Applicant has not disclosed that the specific limitations recited in instant claims are for any particular purpose or solve any stated problem, and the prior art teaches that parameter magnitudes that are encompassed by instant claims, often vary according to the sample being analyzed and various matrices, solutions and parameters appear to work equally as well, absent unexpected results, it would have been obvious for one of ordinary skill to discover the optimum workable ranges of the methods disclosed by the prior art by normal optimization procedures known in the art.
10. Claims 7-8 and 13-16 are rejected under 35 U.S.C. 103 as being unpatentable over Xu (Supra) and Luechau (Supra) as applied to claims 6 and 11-12 above, and further in view of McQueen (March 2019, Frontiers in Chemistry, 7(135): 1-9), McGinnes (02 October 2014, Curr. Protoc. Microbiol., 30), and Trish (12 October 2006, J. Vis. Exp., (1): 49).
Regarding claims 7 and 13-14, Xu and Luechau teach the limitations of claim 6, as discussed supra. All discussions thereon incorporated here. Luechau further teaches “The tube was rotated for 15 min at 22 °C and centrifuged at 1200 × g for 5 min to accelerate phase separation […] Cell paste was resuspended in a slightly hypotonic buffer (10 mM Tris–HCl pH 7.5) at a concentration of 50% wet weight/w and, in order to release B19 particles, cell disruption was supported by short sonication with a microson™ Ultrasonic Cell Disrupter (Heat Systems Inc., New York, USA). To each tube, 0.2 g of the crude feedstock suspension was added so that the final cell paste concentration was 10% wet weight/w. Centrifuge tubes were rotated for 15 min at 22 °C and centrifuged at 1890 × g in a micro centrifuge” (2.5 ATPS experiments, ¶ 1). In summary, Luechau teaches mixing the VLPs and ATPS (rotating), a first centrifugation to accelerate phase separation, resuspending the interface in buffer, and then a second centrifugation after lysis. Neither Xu nor Luechau teaches allowing the mixture to sit before the first centrifugation or dissolving the solid phase in a PBS solution.
However, McQueen teaches “ATPs will spontaneously coalesce into two continuous phases over time by sedimentation according to Stoke's Laws, and physical characteristics such as viscosity slow the process (Asenjo and Andrews, 2012). Centrifugation is often used to accelerate the natural coalescence and sedimentation…” (Page 2, right column, ¶ 2). Therefore, it would have been obvious to one of ordinary skill before the filing date to take the method made obvious by Xu and Luechau and further allowing the mixture to stand before centrifuging, as the result will be predictably the same. The combination of familiar elements is likely to be obvious when it does no more than yield predictable results. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395 – 97 (2007) (see MPEP § 2143, A.). A rationale to support a conclusion that a claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would have yielded nothing more than predictable results to one of ordinary skill in the art. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395 (2007) (see MPEP §§ 2143, A. and 2143.02).
Regarding the dissolution of the solid phase in a PBS solution, McGinnes teaches “Cell supernatants containing released VLPs are cleared of cells and large-sized cell debris by low speed centrifugation.” (Basic Protocol 2: Large Scale Purification of VLPs, ¶ 1) and Trish teaches “First, an expanding culture is washed in PBS to remove residual media and cell debris…” (Abstract). Therefore, it would have been obvious to one of ordinary skill before the filing date to substitute the buffer in McQueen for PBS to remove cell debris, as suggested by McGinnes and Trish. Whether the lysis/extraction is done before or after the addition of the buffer will not affect the end result. The combination of familiar elements is likely to be obvious when it does no more than yield predictable results. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395 – 97 (2007) (see MPEP § 2143, A.). A rationale to support a conclusion that a claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would have yielded nothing more than predictable results to one of ordinary skill in the art. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395 (2007) (see MPEP §§ 2143, A. and 2143.02).
Regarding claims 8 and 15-16, Luechau teaches both centrifugation steps occurring at 22°C, as well as the first centrifugation step taking 5 minutes and the second taking 15 minutes. Regardless, the centrifugation temperature, speeds, and times are all result-effective variables that would be routinely optimized by a person of ordinary skill. It has long been settled to be no more than routine experimentation for one of ordinary skill in the art to discover an optimum value of a result effective variable. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum of workable ranges by routine experimentation." Application of Aller, 220 F.2d 454, 456, 105 USPQ 233, 235-236 (C.C.P.A. 1955). "No invention is involved in discovering optimum ranges of a process by routine experimentation." Id. at 458, 105 USPQ at 236-237. The "discovery of an optimum value of a result effective variable in a known process is ordinarily within the skill of the art." Application of Boesch, 617 F.2d 272, 276, 205 USPQ 215, 218-219 (C.C.P.A. 1980). Since Applicant has not disclosed that the specific limitations recited in instant claims are for any particular purpose or solve any stated problem, and the prior art teaches that parameter magnitudes that are encompassed by instant claims, often vary according to the sample being analyzed and various matrices, solutions and parameters appear to work equally as well, absent unexpected results, it would have been obvious for one of ordinary skill to discover the optimum workable ranges of the methods disclosed by the prior art by normal optimization procedures known in the art.
11. Claims 9-10 and 17-22 are rejected under 35 U.S.C. 103 as being unpatentable over Xu (Supra), Luechau (Supra), McQueen (Supra), McGinnes (Supra), and Trish (Supra) as applied to claims 7-8 and 13-16 above, and further in view of Le Mauff (05 January 2017, Plant Biotechnol., 15(3): 285-296) and Laboru (01 November 2020, Protein Downstream Processing, Chapter 9, pages 89-100).
Regarding claims 9 and 17-22, Xu, Luechau, McQueen, McGinnes, and Trish make claims 6-8 and 11-14 obvious, as discussed supra. All discussions thereon incorporated here. None of the references teach preparing the crude extract by infecting a plant tissue with Agrobacterium containing a viral plasmid, crushing and extracting the plant tissue with TBE, and then centrifuging the product.
However, Le Mauff teaches “In this study, we have investigated the alteration of the biochemical composition of the cell walls of N. benthamiana leaves subjected to abiotic and biotic stresses induced by the Agrobacterium-mediated transient transformation and the resulting high expression levels of influenza VLPs.” (Abstract). The Agrobacterium were transformed with plasmids encoding the Influenza H1 protein (Experimental procedures, ¶ 1). Therefore, it would have been obvious to one of ordinary skill before the filing date to use the VLPs made by Le Mauff in the VLP separation and purification method made obvious supra. The combination of familiar elements is likely to be obvious when it does no more than yield predictable results. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395 – 97 (2007) (see MPEP § 2143, A.). A rationale to support a conclusion that a claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would have yielded nothing more than predictable results to one of ordinary skill in the art. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395 (2007) (see MPEP §§ 2143, A. and 2143.02).
Regarding the extraction in TBE, Laboru teaches “Collect the aerial parts (first and second stem and leaves) of the plant before flowering and immediately ground using liquid nitrogen with a previously frozen mortar and pestle… Protein extraction is performed using TBE buffer at a proportion of 1.0 g powdered alfalfa per 10 ml buffer. The slurry is stirred for 1.0 h and then centrifuged at 12,000 × g for 10 min at room temperature.” (Page 93, ¶ 2-3). Therefore, it would have been obvious to apply the extraction method of crushing, extracting in TBE, and centrifuging to the N. benthamiana leaves of Le Mauff. The combination of familiar elements is likely to be obvious when it does no more than yield predictable results. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395 – 97 (2007) (see MPEP § 2143, A.). A rationale to support a conclusion that a claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would have yielded nothing more than predictable results to one of ordinary skill in the art. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395 (2007) (see MPEP §§ 2143, A. and 2143.02).
Regarding claim 10, Laboru teaches “Green tissue protein extraction buffer: Tris–borate–ethylenediaminetetraacetic acid (EDTA) (TBE) buffer, pH 8: 0.45 M Tris–HCl, 0.45 M H3BO3, 10 mM EDTA, pH 8.0.” and discussed water being added to the buffer (Page 90, last ¶).
Conclusion
12. No claim is allowed. Any inquiry concerning this communication or earlier communications from the examiner should be directed to KRISTINA E LY whose telephone number is (571)272-5169. The examiner can normally be reached Monday - Thursday, 8:00 am - 5:00 pm EST.
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/KRISTINA E. LY/Examiner, Art Unit 1671 /Michael Allen/Supervisory Patent Examiner, Art Unit 1671
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