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 .
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
This Action is in response to the papers filed on 08/18/2026. Claims 9-12, 14, 24-25, 31, 39-40, 42-45, 49-58 are currently pending. Claims 9-10, 12, 14, 49-54 have been amended, claims 56-58 have been newly added, and claims 32-38 has been cancelled by Applicant’s amendment filed on 08/18/2026.
Election/Restrictions
Applicants’ election of Group II, which include claims 9-12 and 14 drawn to a method of enrichment of small airway and alveolar epithelia progenitor cells from distal lung tissue in the reply filed on 02/04/2026 was previously acknowledged. Because applicant did not distinctly and specifically point out the supposed errors in the restriction requirement, the election was treated as an election without traverse (MPEP § 818.01(a)). Claims 49-58 also read on the elected invention.
Claims 24-25, 31-32, 34-37, 39-40, and 42-45 (32-37 cancelled) were previously withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to non-elected subject matter, there being no allowable generic or linking claim. The requirement for restriction was previously made final.
Therefore, claims 9-12, 14, 49-58 are currently under examination to which the following grounds of rejection are applicable.
Priority
The instant application a 371 of PCT/US2021/030280 filed 04/30/2021, which claims priority to PCT/US2021/030280 filed 07/21/2020. PCT/US2021/030280 claims priority to PRO 63/054,440, PRO 63/019,217, and PRO 63/019,140 all filed on 05/01/2020.
Thus, the earliest possible priority for the instant application is 05/01/2020.Information Disclosure Statement
The information disclosure statements (IDS) submitted on 08/18/2026 were filed before the mailing date of the non-final office action. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Withdrawn Rejections in response to Applicants’ arguments or amendments
Claim Rejections - 35 USC § 112(b)
The rejection of claims 9-12, 14, and 49-54 under 35 USC § 112(b) is withdrawn in view of the amendments in the response filed on 08/18/2026. Applicants’ arguments with regard to a withdrawn objection/rejection are moot.
Maintained and modified objections/rejections in response to Applicants’ arguments or amendments
Claim Objections
Claim 9 remains objected to because the recitation of “freezing the about 0.5-5.0 mm diameter pieces lung tissue” in line 14 and “thawing the frozen about 0.5-5.0 mm diameter pieces lung tissue” is grammatically incorrect. Appropriate correction is required.
Claim Rejections - 35 USC § 112
Claim 55 remains 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 applicant regards as the invention.
Claim 55 recites “The method of claim 9, wherein selecting epithelial progenitor cells comprising depleting immune cells and endothelial cells, cell surface staining for Fluorescence associated cell sorting (FACS), or both.” However, as written it is unclear whether FACS sorting is actually performed or if only the staining for FACS sorting is performed. This lack of clarity renders the claim indefinite as one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. As such the metes and bounds of the claim are indefinite.
Claim Rejections - 35 USC § 103
Claims 9-12, 14, 49-50, 52-55 remain rejected and claims 56-58 are newly rejected under 35 U.S.C. 103 as being unpatentable over Zacharias et al. (William Zacharias et al., Protocol exchange, 2018; hereafter “Zacharias”) in further view of Prada et al. ( M Llamazares Prada, et al., bioRxiv, April 4th, 2020; hereafter “Prada”) as evidenced by Barkauskas et al. (Barkauskas CE et al., Development, 2017).
This modified rejection is necessitated in response to the claim amendments filed 08/18/2026.
Regarding claims 9-11 and 52, The instant claim 9 is drawn to a method with the following requirements: cutting distal lung tissue into about 0.5cm3 to 2.0 cm3 pieces, washing the cut lung pieces, removing visceral pleura from the cut lung pieces, cutting the pieces into 0.5-5.0mm diameter pieces, freezing and then thawing the 0.5mm-5.0mm pieces, cutting the thawed pieces again into 0.5-1.5mm diameter pieces, digesting the 0.5-1.5mm diameter pieces with enzyme, dissociating the digested pieces into single cells, and then selecting epithelial progenitor cells. Claims 10-11 are drawn to cutting the 0.5-1.5mm diameter pieces of lung tissue of claim 9 into progressively small pieces of specific size. Claim 52 is drawn to cutting the 0.5 cm3 to 2.0 cm3 pieces of lung tissue of claim 9 into 1.0 cm3.
Zacharias teaches a method for Isolation and culture of human alveolar epithelial progenitor cells (Title). Specifically, Zacharias teaches “Here we describe the techniques used for isolation and 3D organoid formation of alveolar epithelial progenitor cells from primary human lungs. We describe the selection, digestion, single cell suspension, antibody staining, and culture techniques used for these assays.” (Abstract). Zacharias teaches removal of the visceral pleura and emphasis the importance to do so to prevent negatively effecting the digestion (Pg. 2, Procedure Section). Zacharias teaches cutting the lung tissue into progressively smaller pieces (Pg. 2, Procedure Section). Digestion using enzyme solution containing collagenase, dispase, and DNase. (Pg. 2, Procedure, second line). Zacharias teaches bead sorting to select alveolar epithelial progenitor cells (Pg. 3, from step 19.) Thus, Zacharias teaches digesting human lung tissue with enzyme, dissociating the digested tissue into single cells, and selecting epithelial progenitor cells from distal/alveolar lung tissue.
Zacharias does not teach the lung tissue pieces are cut into pieces of the exact diameter ranges recited in the instant claims or require freezing and thawing before processing.
Prada teaches cryopreservation of human lung tissue pieces followed by downstream cell typing analysis. Prada teaches the removal of pleura from lung tissue, separation of airway and vessels from lung parenchyma, and that the parenchymal airway and vessel free fraction is minced into 4x4mm pieces, which are then transferred to cryopreservation tubes and cryopreserved (Pg. 16-17, 2nd-3rd Method sections). Thus, Prada teaches freezing, thawing, and then processing lung pieces to obtain live epithelial cells.
It would have been obvious to a person having ordinary skill in the art at the time of the instant application to modify the method taught by Zacharias for isolating human alveolar epithelial progenitor cells, by incorporating cryopreservation as taught by Prada. One would have been motivated to combine these teachings to provide a method that would be suitable for storage, batching, shipment, and delayed processing of human lung samples. This would avoid the need for same day digestion/processing while preserving tissue for downstream cell isolation and profiling. Prada demonstrates that cryopreserved human lung tissue can be used to successfully obtain viable cells, including epithelial cells, for downstream analysis.
Furthermore, one having ordinary skill in the art would understand the need to cut smaller pieces of lung tissue from larger pieces of lung tissue (as recited in the instant claims 9-11 and 52) for more efficient digestion and filtration of tissue. Moreover, a person of ordinary skill in the art would have been motivated to determine an appropriate size of lung tissue through routine optimization within a method for isolation of primary cells from tissue that would allow for the most successful digestion and filtration without having clogs to achieve a desired population of viable cells. See MPEP 2144.05 II. A. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) (Claimed process which was performed at a temperature between 40°C and 80°C and an acid concentration between 25% and 70% was held to be prima facie obvious over a reference process which differed from the claims only in that the reference process was performed at a temperature of 100°C and an acid concentration of 10%.); see also Peterson, 315 F.3d at 1330, 65 USPQ2d at 1382 ("The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages.").
Regarding Claim 12, Zacharias teaches digestion using enzyme solution containing collagenase, dispase, and DNase. (Pg. 2, Procedure, second line).
Regarding Claim 14, Zacharias teaches the population of cells selected from their method to be HTII-280-positive, specifically “This population of cells are HT280+Tm4sf1+ human AEPs.” (Pg. 4, line 12).
Regarding Claim 49, Zacharias and Prada together teach the method of claim 9 as discussed above.
As Zacharias teaches isolating alveolar epithelial progenitor cells from human lung tissue and Prada teaches separating lung tissue into compartmental fractions such as airway/vessel enriched tissue and airway-free parenchymal tissue before processing, cryopreserving, and cell typing, it would have been obvious to one of ordinary skill in the art to select and process the region of tissue containing the cells of interest to provide a starting material enriched for the desired distal/alveolar epithelial population. Furthermore, it was well known in the art prior to the instant application that proximal and distal regions of the lung contain specific cell populations specialized for different functions. This is evidenced by the teachings of Barkauskas et al. (Abstract, Introduction).
Regarding Claims 50 and 53, Prada teaches transferring minced human lung tissue pieces into cryotubes and transferring cryotubes to -80 degrees Celsius (Pg. 16-17, 2nd-3rd Method sections). This reads on the temperatures as recited in claims 50 and 53.
Regarding Claim 54, the alveolar epithelial progenitor cells isolated by the method of Zacharias and Prada would inherently be CD45- absent evidence to the contrary as CD45+ is a pan leukocyte marker and alveolar epithelial progenitor cells are distinct cell type that are not leukocytes. Moreover, Prada specifically teaches using FACS to determine CD45 status (Pg. 8, Section: Multiple cell types can be isolated from cryopreserved lung tissue) and describes selection of CD45- EpCAM+/CD45− cells (Pg. 6, 1st Paragraph).
Regarding Claim 55, Zacharias teaches their method to include FACs sorting of cells (Pg. 3-4, beginning from step 16). Moreover, Prada teaches within their methods the use of FACs sorting of cells for cell typing analysis (Pg. 8, Final Paragraph – Pg. 9, Paragraphs 1-2)
Regarding Claim 56, Zacharias and Prada render obvious the method of claim 9 as provided in the 103 rejection above, the contents of which are incorporated herein in their entirety.
Moreover, Prada teaches recovery and sorting analysis of viable cells from cryopreserved human lung tissue (Pg. 19, Immunofluorescence method section).
It would have been obvious to a person having ordinary skill in the art at the time of the instant application filing to use DAPI staining as taught by Prada, to select DAPI-negative (viable) cells. One having ordinary skill in the art would have a reasonable expectation of success as the use of DAPI to stain and exclude non-viable cells for experimentation is a routine flow-cytometry method for selecting viable cells that was well known in the art to one having ordinary skill before the filing of the instant application.
Regarding Claim 57-58, Zacharias and Prada render obvious the method of claim 9 as provided in the 103 rejection above, the contents of which are incorporated herein in their entirety. As discussed in the rejection of claim 9 above, Prada teaches lung pieces cut into 4x4mm pieces which reads on the diameter recites in the instant claims 57-58.
Claim 51 remains rejected under 35 U.S.C. 103 as being unpatentable over Zacharias et al. (William Zacharias et al., Protocol exchange, 2018; hereafter “Zacharias”) in further view of Prada et al. ( M Llamazares Prada, et al., bioRxiv, April 4th, 2020; hereafter “Prada”) as applied to claims 9 and 50 above and in view of Andreasen et al. (US11484025B2; hereafter “Andreasen”).
This modified rejection is necessitated in response to the claim amendments filed 08/18/2026.
Regarding Claim 51, Zacharias and Prada render obvious the method of claims 9 and 50 as provided in the 103 rejection above, the contents of which are incorporated herein in their entirety.
Although Prada teaches transferring minced human lung tissue pieces into cryotubes and transferring cryotubes to -80 degrees Celsius and then kept in liquid nitrogen from long term storage (Pg. 16-17, 2nd-3rd Method sections), the combined teachings of Zacharias and Prada do not expressly teach the use of vapor phase nitrogen gas within their methods.
Andreasen cures the deficiencies of Zacharias and Prada as Andreasen teaches cryopreservation methods of tissue (Column 1, Background of the Invention Section), including lung (Column 7, lines 47-48). Freezing can be done to about -80 degrees C and freezing can further be done in liquid nitrogen or vapor phase (Column 24, lines 3-7).
It would have been obvious to a person having ordinary skill in the art at the time of the instant application to have modified the method for isolating cells from lung tissue as described by Zacharias and Prada to further include the step of a cryopreservation method as taught by Andreasen. One would be motivated to freeze isolated cells to allow for future experimentation or cell culture of the isolated cells as is done routinely in the art. There would have been reasonable expectations of success in combining these teachings as one of ordinary skill in the art would recognize to combine known elements in the art to give predictable results.
Response to Applicants’ Arguments as they apply to the modified rejection of claims 9-12, 14, 49-55 which remain rejected and newly rejected claims 56-58 under 35 U.S.C. 103
At pages 8-12 of the remarks, Applicants essentially argue that the evidence of solving the needs in the art and having the greater than expected results as compared to cryopreserved dissociated cells, such as not needing to immediately isolate and freeze all the lung cells and being able to maintain the cell types from the original lung tissue shows that the claimed method is not obvious.
These arguments have been considered but have not been found persuasive.
At Pg. 9 applicant argues the following: “Applicant respectfully submits that the claimed method solves a need in the art and has greater than expected results. As discussed in the background section of the present application, the "current state of the art for cryopreservation relating to the lung involves isolating cells from whole lung and freezing down all the cells for future experiment and to share collaborators and interested professionals." (Emphasis added.)”
These arguments were provided by the applicant in consideration of the combined prior art teachings of Zacharias and Andreason as provided in the non-final office action for the 103 rejections as filed 05/21/2026. However, the amended claims filed on 08/18/2026 necessitated modification of the maintained 103 rejections. The modified 103 rejection provided in this final action provide the teachings of Prada et al. in combination with Zacharias, which together render the claims obvious. Prada is directed towards cryopreservation of human lung tissue, including storage of lung tissue with high viability and downstream cell type profiling from cryopreserved lung samples. Prada also teaches human lung dissection and preparation for cryopreservation and reports viable cell recovery from cryopreserved lung tissue.
Thus, the applicants’ arguments are not found persuasive.
New rejections in response to Applicants’ arguments or amendments
Claim Rejections - 35 USC § 112
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.
Claim 56 rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 56 recites “…wherein selecting the epithelial progenitor cells comprising
selecting cells having a surface marker profile that is negative for DAPI.” It is unclear what the applicants’ intended meaning is for the claim as DAPI is a DNA binding dye and not a surface marker. Therefore, the claim is indefinite. Applicant should amend to clarify exactly what they intend to claim.
Conclusion
Claims 9-12, 14, 49-58 are rejected.
Applicants’ amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KODYE LEE ABBOTT whose telephone number is (703)756-1111. The examiner can normally be reached M-F 8-5.
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/KODYE LEE ABBOTT/Examiner, Art Unit 1634
/MARIA G LEAVITT/Supervisory Patent Examiner, Art Unit 1634
