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 .
Response to Amendment
The amendment filed 5/14/2026, amending claims 1 and 9 and cancelling claim 4 is acknowledged. Applicant’s amendments to the claims have overcome the claim objection, 112(a) rejection, 112(b) rejections, 112(d) rejection, 102 rejection of claim 1 as being anticipated by Dominici, and 103 rejection of claim 9 as being unpatentable over Dominici in further view of Yuan as previously set forth in the Non-Final Office Action mailed 11/17/2025.
Newly amended claim 1 now requires the cellular particle to comprise particle with a closed circular membrane with soluble TRAIL in their lumen with anti-cancer activity, which is not disclosed by Dominici.
Applicant’s amendment’s to claim 1 clarify that the anti-cancer activity is specifically attributable to soluble TRAIL contained within the cellular particulate.
Claims 1 and 5-9 are pending.
Claims 1 and 9 are pending and under examination.
Claim Rejections - 35 USC § 112(a) – Written Description; New, necessitated by amend.
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1 and 9 are rejected 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. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claim 1 recites a method for the production of cellular particulate with antitumor activity, wherein it comprises isolating the cellular particulate from a supernatant collected from a cell population culture,
wherein the cellular particulate comprises particles that have a closed circular membrane formed by a double layer consisting partially or entirely of phospholipids;
wherein said particles have soluble TRAIL in their lumen with anti-cancer activity;
wherein the cell population is a human adipose tissue derived pericytes (AD-PC), and
wherein the cells are transduced in a stable manner with a retroviral vector encoding soluble Tumor necrosis factor-Related Apoptosis-Inducing Ligand (TRAIL), wherein the cells express an antitumor soluble TRAIL.
In analyzing whether the written description requirement is met for genus claims, it is first determined whether a representative number of species have been described by their complete structure. To provide adequate written description and evidence of possession of a claimed genus, the specification must provide sufficient distinguishing identifying characteristics of the genus. The factors to be considered include disclosure of complete or partial structure, physical and/or chemical properties, functional characteristics, structure/function correlation, methods of making the claimed product, or any combination thereof. The disclosure of a single species is rarely, if ever, sufficient to describe a broad genus, particularly when the specification fails to describe the features of that genus, even in passing. (see In re Shokal 113USPQ283(CCPA1957); Purdue Pharma L.P. vs Faulding Inc. 56 USPQ2nd 1481 (CAFC 2000).
The court explained that “reading a claim in light of the specification, to thereby interpret limitations explicitly recited in the claim, is a quite different thing from ‘reading limitations of the specification into a claim,' to thereby narrow the scope of the claim by implicitly adding disclosed limitations which have no express basis in the claim.” The court found that applicant was advocating the latter, i.e., the impermissible importation of subject matter from the specification into the claim.). See also In re Morris, 127 F.3d 1048, 1054-55, 44 USPQ2d 1023, 1027-28 (Fed. Cir. 1997).
The instant specification provides little guidance on isolating cellular particulate comprising particles that have a closed circular membrane formed by a double layer consisting partially or entirely of phospholipids, with said particles have soluble TRAIL in their lumen with anti-cancer activity.
The specification describes “cellular particulate” as “a product of cellular activity consisting of particles that are released spontaneously outside the cell. These particles are delimited by a closed circular membrane consisting entirely or partially of phospholipids. Furthermore, they are characterized by a diameter size comprised between 40 nm and 5000 un. The cellular particulate can originate from protuberances of the plasma membrane which subsequently detach from it. Alternatively, the cellular particulate can originate within intracellular organelles known as endosomes, and subsequently be released outside the cell by fusion of the endosomal membrane with the plasma membrane. Alternatively, the cellular particulate can originate from protrusions of the plasma membrane during the process of cellular apoptosis.” (pg. 1-2).
Regarding “lumen”, pg. 2 of the specification recites “It is known that the cellular particulate can include, in the lumen or in the membrane of the particles of which it consists, molecules deriving from the cell that produced it.”
The limitation of particles having sTRAIL in their lumen with anti-cancer activity merely states a functional characteristic without providing any indication about how the functional characteristic is provided. The functional characteristic does not follow from (is not an inherent property of) the structure recited in the claim, so it is unclear whether the claim requires some other structure to be added to the composition to provide the functional characteristic. The specification fails to disclose what structural changes to the method is necessary and sufficient to cause the recited isolated cellular particulate comprising particles that have a closed circular membrane formed by a double layer consisting partially or entirely of phospholipids to have sTRAIL in their lumen with anti-cancer activity, and thus the ordinary artisan would not know what modification(s) must be made in order to fulfill the instant recitation.
The claims fail to recite, and the specification fails to disclose a first isolated cellular particulate comprising particles that have a closed circular membrane formed by a double layer consisting partially or entirely of phospholipids, that is unable to have sTRAIL in their lumen with anti-cancer activity, as opposed to a second isolated cellular particulate comprising particles that have a closed circular membrane formed by a double layer consisting partially or entirely of phospholipids that is necessarily and predictably capable of having sTRAIL in their lumen with anti-cancer activity, for example.
The working examples of the instant specification provides little guidance for an artisan to isolate cellular particulate comprising particles that have a closed circular membrane formed by a double layer consisting partially or entirely of phospholipids, with said particles have soluble TRAIL in their lumen with anti-cancer activity.
Example 1 teaches isolating cellular particulate produced by AD-PC by centrifugating and filtering the supernatant, with the resulting pellet being re-suspended in an appropriate medium (pg. 6). Afterwards, the obtained cellular particulate (i.e., pellet re-suspended in medium) is stained with CFDA-SE before displaying microvesicles (MVs) in flow cytometer. The specification notes that CFDA-SE is a dye able to penetrate into the cell cytoplasm where it is converted by intracellular esterase into CFSE, which is retained inside cells bound to intracellular proteins. Therefore, CFDA-SE allow to distinguish closed structures, coated by membrane, in this case the cellular particulate, from cellular debris.
In view of Example 1, it is unclear how cellular particulate as recited in the claimed method differs from centrifuged and filtered supernatant. Further, the teachings of Example 1 suggest that simply centrifugating and filtering the supernatant produced by AD-PC would result in the recited cellular particulate comprising particles that have a closed circular membrane formed by a double layer consisting partially or entirely of phospholipids, with said particles have soluble TRAIL in their lumen with anti-cancer activity.
In Example 2, following the resuspension of the isolated cellular particulate and lysis of the particulate itself, quantification of TRAIL content using the ELISA test showed the presence of TRAIL in the particulate deriving from AD-PC-TRAIL. The Applicant concludes from Example 2 that “As is known, AD-PC-TRAIL produce a soluble TRAIL molecule lacking the structural elements necessary to insert the particles that form the cellular particulate into the membrane. Therefore, the TRAIL molecules detected are originally localized in the lumen of the particles that form the particulate.” (pg. 7). However, the specification fails to expand further upon how this conclusion is drawn, and when the TRAIL would not be localized in the lumen with anti-cancer activity, for example.
The art teaches using CFDA-SE to stain cells to study cell proliferation. For example, BenchChem teaches that CFDA-SE is a cell-permeable dye that is widely used for long-term cell tracking and proliferation studies. As cells divide, the resulting CFSE label, from intracellular esterases cleaving the acetate groups of CFDA-SE, is distributed approximately equally between daughter cells, resulting in a successive halving of fluorescence intensity with each cell division. BenchChem is silent on the use of CFDA-SE to track particles in cellular particulate.
Additionally, a search of the art did not return any specific teachings or guidance on further isolating particles with TRAIL in their lumen with anti-cancer activity from supernatant.
The prior art does teach conditioned medium and supernatant comprising TRAIL having anti-cancer activity. For example, Menon et al. (Menon, Lata G., et al. "Human bone marrow-derived mesenchymal stromal cells expressing S-TRAIL as a cellular delivery vehicle for human glioma therapy." Stem cells 27.9 (2009): 2320-2330.) transduced hMSCs with a lentivirus expressing secretable TRAIL (S-TRAIL) (Abstract). To assess the bioactivity of secreted S-TRAIL, the conditioned medium of hMSC S-TRAIL cells was added to U87 (glioma) cells (pg. 2322, col 1, “Bioactivity of S-TRAIL Protein in Culture Medium”). After 96 hours of exposure, only 15% of glioma cells were viable, indicating the cytotoxicity of S-TRAIL in conditioned medium on tumor cells (pg. 2326, col 1, para 2). Menon et al. is silent on the presence of particles in the supernatant/cellular particulate.
Thus, in light of the lack of guidance in the specification and the art on cellular particulate comprising particles that have a closed circular membrane formed by a double layer consisting partially or entirely of phospholipids, with said particles have soluble TRAIL in their lumen with anti-cancer activity, how one would determine the presence of these particles, and what conditions they would/would not be present under, the artisan would not have understood the Applicant to have been in possession of the invention as claimed.
Claim Rejections - 35 USC § 112(b) – New, necessitated by amendment
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1 and 9 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
A broad range or limitation together with a narrow range or limitation that falls within the broad range or limitation (in the same claim) may be considered indefinite if the resulting claim does not clearly set forth the metes and bounds of the patent protection desired. See MPEP § 2173.05(c). In the present instance, claim 1 recites the broad recitation “partially or entirely”, and the claims also recite “consisting”, which is the narrower statement of the range/limitation. The claim(s) are considered indefinite because there is a question or doubt as to whether the feature introduced by such narrower language is (a) merely exemplary of the remainder of the claim, and therefore not required, or (b) a required feature of the claims.
For examination purposes, the recitation “consisting partially or entirely of” is interpreted to read on particles that have a closed circular membrane formed by a double layer that comprises phospholipids.
Claim 9 recites the limitation "the pellet" in line 5. There is insufficient antecedent basis for this limitation in the claim. The recitation is indefinite because there is no prior reference to a pellet in claim 9, and there is nothing implicit in claim 1, from which claim 9 depends upon, that would inherently require a pellet. Therefore, the metes and bounds of the claim is not clearly and precisely defined. It would be remedial to amend claim 9 to recite “resuspending a resulting pellet containing the cellular particulate”.
Claim Rejections - 35 USC § 103 – New, necessitated by amendment
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1 and 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over
Dominici (US20150320803A1, published 11/12/2015) and in further view of Yuan (Yuan, Z., Kolluri, K. K., Gowers, K. H., & Janes, S. M. (2017). TRAIL delivery by MSC-derived extracellular vesicles is an effective anticancer therapy. Journal of extracellular vesicles, 6(1), 1265291.) and Gaceb et al. (Gaceb, Abderahim et al. “Pericytes secrete pro-regenerative molecules in response to platelet-derived growth factor-BB.” Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism vol. 38,1 (2017 Jul 25): 45-57. doi:10.1177/0271678X17719645).
Dominici teaches a method for the production of soluble TRAIL (sTRAIL), an anti-tumor TRAIL protein (e.g., Abstract, [0041]). A retroviral vector comprising sTRAIL was used to transduce pericytes isolated from adipose tissue (e.g., [0103]). Following transduction, when looking at the Western Blot image (FIG. 7) the TRAIL protein band can be identified both in the cell lysate of AD-PCΔTRAIL, confirming the presence of the protein at intracytoplasmatic level, and in the supernatant (e.g., in cellular particulate), confirming that, once the protein has been produced by the cell, it is excreted into and extracytoplasmatic environment (e.g., [0111]) The anti-tumor activity is specifically exerted by the TRAIL excreted by infected AD-PC cells (e.g., [0122]).
Dominici teaches collecting the retroviral supernatant for further use, such as to supplement other mediums (e.g., [0094])
Dominici teaches that it has previously been demonstrated that pro-apoptotic molecule TRAIL delivered by human pericytes extracted from adipose tissue (AD-PC) is particularly active to induce tumor cell apoptosis in several different epithelial and mesenchymal cancer types (e.g., [0031]).
Dominici is not explicit about the presence of particles that have a closed circular membrane formed by a double layer consisting partially or entirely of phospholipids, with said particles having soluble TRAIL in their lumen with anti-cancer activity.
An artisan, interested in anticancer therapies using TRAIL, would be aware of Yuan et al. for teaching TRAIL delivery by MSC-derived extracellular vesicles.
An artisan, interested in pericyte-derived vesicles, would be aware of Gaceb et al. (Gaceb, Abderahim et al. “Pericytes secrete pro-regenerative molecules in response to platelet-derived growth factor-BB.” Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism vol. 38,1 (2018): 45-57. doi:10.1177/0271678X17719645) for characterizing microvesicles released by pericytes.
Yuan teaches transducing MSCs with lentiviruses comprising full-length TRAIL, resulting in the transduced cell population releasing extracellular vesicles (EVs), which are lipid membrane-enclosed nanoparticles of 50-70 nm in diameter released by cells (i.e., cellular particulate comprising particles with close circular membrane formed by double layer comprising phospholipids) (e.g., Abstract). TRAIL-expressing MSCs were cultured in a medium. The cell culture medium was then collected and centrifuged to remove cells and debris. The resulting medium (i.e., supernatant) was then vacuum-filtered to remove large vesicles, and finally ultracentrifuged, resulting in isolated EVs (e.g., pg. 2, Methods and Materials, “Isolation of EVs”).
Yuan teaches centrifuging the isolated cell particulate (i.e., EVs) for 10 min at 300xg and then again at 2000xg at 4 degrees Celsius, followed by vacuum filtering the medium through 0.22 micrometer filters (i.e., filtering by gravity), followed by ultracentrifuging for 2 hours at 100,000xg at 4° Celsius (e.g., pg. 2, “Isolation of EVs”).
Gaceb et al. teaches that pericytes share many features with MSCs, such as surface marker expression and mesodermal differentiation capacity (e.g., last para pg. 45-first para pg. 46). Microvesicles (MVs) allow the emitting cell to modify gene and protein expression in the receiving cell and enable cell communication over long distances (e.g., pg. 46, para 2). In response to PDGF-BB, brain-derived pericytes secrete MVs (e.g., pg. 46, para 2). To isolate the MVs, cell medium was centrifuged at 1500g for 5min and the supernatant free from cells debris was collected. In order to pellet MVs, the supernatant was centrifuged at 16,000g for 45min. For quantification, MVs were analyzed by flow cytometry (flow cytometer with an Accuri C6; BD Biosciences) using flow count beads (Beckman Coulter). The region corresponding to the total number of MVs was identified in FSC and SSC intensity dot plot representation, set at logarithmic gain, according to their diameter (0.1–1mm), compared to the beads size (e.g., pg. 47, “Microvesicle preparation and quantification”).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to apply the knowledge that pericytes secrete MVs to the teachings of Dominici, as well as combine the method of isolating cellular particulate from supernatant taught by Yuan, with the method for the production of cellular particulate with antitumor activity taught by Dominici to arrive at the claimed invention. One would have a reasonable degree for success for the combination of Dominici and Yuan because both Yuan and Dominici teach methods of transducing and culturing cells with retroviruses, Gaceb et al. teaches that pericytes secrete MVs, like the MSCs taught by Yuan, and both Yuan and Dominici teach collecting supernatant. One would be motivated to apply the teachings of Gaceb et al. and Yuan to Dominici because as taught by Dominici, the pro-apoptotic molecule TRAIL delivered by human pericytes extracted from adipose tissue (AD-PC) is particularly active to induce tumor cell apoptosis in several different epithelial and mesenchymal cancer types including cervical carcinoma, pancreas, colon, multiple myeloma, osteosarcoma, rhabdomyosarcoma and Ewing's sarcoma. (e.g., [0031]).
Additionally, the instant specification fails to disclose an element of criticality of the speed and length of centrifugation, as well as the filter size (e.g., there is no disclosure of the importance of the initial centrifugation being at 2,000 g for 20 minutes versus 10 min at 300g +10 mins at 2000 g). There is nothing to suggest that the method of isolation taught by Yuan structurally changes the isolated particles, and would not result in the same isolated particles as the claimed method.
Further, it is proper to "take account of the inferences and creative steps that a person of ordinary skill in the art would employ." KSR Int'l Co. v. Teleflex Inc., 127 S. Ct. 1727, 1741,82 USPQ2d 1385, 1396 (2007). See also Id. At 1742, 82 USPQ2d 1397 ("A person of ordinary skill is also a person of ordinary creativity, not an automaton.").
It should be noted that the KSR case forecloses the argument that a specific teaching, suggestion, or motivation is required to support a finding of obviousness. See the recent Board decision Ex parte Smith, —USPQ2d—, slip op. at 20, (Bd. Pat. App. & Interf. June 25, 2007) (citing KSR, 82 USPQ2d at 1396) (available at http:www.uspto.gov/web/offices/dcom/bpai/prec/fd071925 .pdf).
The cited prior art meets the criteria set forth in both Graham and KSR, and the teachings of the cited prior art provide the requisite teachings and motivations with a clear, reasonable expectation of success. Thus, the invention as a whole is prima facie obvious.
Response to Arguments
Applicant's arguments filed 5/14/2026 have been fully considered but they are not persuasive.
In response to applicant's argument that Dominici focuses on soluble TRAIL released from the modified cells themselves, rather than on isolation of a distinct cellular particulate product carrying soluble TRAIL, a recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim.
The applicant argues Dominici does not disclose isolating cellular particulate from AD-PC-TRAIL culture supernatant, does not disclose particles having a closed circular phospholipid membrane structure, and does not disclose soluble TRAIL being located within the lumen of such particles. Nor does Dominici disclose that such isolated particulate itself possesses the claimed anti-cancer activity. These arguments are not persuasive because Dominici teaches isolating AD-PC-TRAIL culture supernatant (e.g., [0099] “quantification of the ΔTRAIL amount released by the cells of the supernatant.”, [0100], etc.- ΔTRAIL amount released reads on cellular particulate). Additionally, Dominici disclose that such isolated particulate itself possesses the claimed anti-cancer activity (e.g., [0122] “confirms that the mortality encountered with treated tumor cells is really mediated by the anti-tumor action exerted by the TRAIL excreted by infected AD-PC cells”).
While Dominici is silent on the particles having a closed circular phospholipid membrane structure, and the soluble TRAIL being located within the lumen of such particles, there is no evidence that the supernatant (i.e., cellular particulate) of Dominici would not also possess these particles. Like the instant specification, Dominici teaches transducing AD-PCs with a retrovirus comprising sTRAIL. Both Dominici and the instant specification teach isolating the supernatant resulting from culturing AD-PC-sTRAIL cells. The only difference is the instant specification explicitly tests the supernatant for the particles. Absent evidence to the contrary, an artisan could reasonable conclude that the supernatant of Dominici would also have these particles if evaluated.
The applicant argues that Yuan uses a materially different protocol than amended claim 9. This argument is not persuasive because it does not provide evidence for the criticality of using the exact centrifugation speed and time recited, as well as the filter size used. Additionally, the applicant fails to distinctly point out why an artisan cannot apply the isolation method taught by Yuan to the supernatant taught by Domicini with a reasonable expectation of success.
Conclusion
No claims are allowed.
Applicant's 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.
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/ALLISON MARIE JOHNSON/Examiner, Art Unit 1638
/ROBERT M KELLY/Primary Examiner, Art Unit 1638
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