Patent Application 18614283 - CELL CULTURE LASER PHOTOABLATION

Title: CELL CULTURE LASER PHOTOABLATION

Application Information

Invention Title: CELL CULTURE LASER PHOTOABLATION
Application Number: 18614283
Submission Date: 2025-04-10T00:00:00.000Z
Effective Filing Date: 2024-03-22T00:00:00.000Z
Filing Date: 2024-03-22T00:00:00.000Z
Examiner Employee Number: 87912
Art Unit: 1657
Tech Center: 1600

Rejection Summary

102 Rejections: 0
103 Rejections: 3

Cited Patents

No patents were cited in this rejection.

Office Action Text

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 Response of 31 March 2025 has been entered.
Claims 21-41 are currently pending.

Election/Restrictions
Applicant’s election of the species of: a biomarker as the basis for selection; and a cell surface receptor as the biomarker in the reply filed on 31 March 2025 is acknowledged. Because applicant did not distinctly and specifically point out the supposed errors in the restriction requirement, the election has been treated as an election without traverse (MPEP § 818.01(a)).
Claims 27-31, 33, 34 and 37-39 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected species, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 31 March 2025.
Claims 21-26, 32, 35, 36, 40 and 41 are considered here.

Claim Rejections - 35 USC § 103
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.

Claims 21-23, 26 and 40 are rejected under 35 U.S.C. 103 as being unpatentable over Koller et al., Cytometry Part A: The Journal of the International Society for Analytical Cytology 61.2 (2004): 153-161 (cited in IDS of 22 March 2024).
Regarding claims 21, 22, 26 and 40, Koller teaches a method comprising: a) providing cells in each of two or more partitioned surfaces or containers (wells of a 384-well plate); b) selecting a cell in each of the two or more partitioned surfaces or containers to retain, thereby identifying a selected cell; and c) laser photoablating all of the cells in each of the two or more partitioned surfaces or containers except the selected cell (entire doc, including under Materials and Methods; and Results, esp. under In Situ Cloning of GFP-Transfected 293T Cells). Koller teaches that the photoablation method can be used as a high-throughput method for sorting and purifying a wide variety of cell types (under Discussion). The method was utilized for selecting a high-expressing recombinant cell for purposes of clonal selection, wherein the cell was transfected with a GFP plasmid and a high-expressing cell was selected in each well based on the brightest fluorescence intensity (under In Situ Cloning of GFP-Transfected 293T Cells; Fig. 5). Regarding the recitation in claim 21 that “cells are photoablated at a rate of at least 60 cells per second”, Koller teaches that the photoablation is carried out with an automated image analysis/laser system capable of imaging 250000 cells/second and with a laser firing at greater than 1000 times/second with pulses in the nanosecond range (p. 154, under The LEAP Instrument Platform; p. 155-156, under Comparison of Difference Mechanisms for Laser-Mediated Cell Purification). While Koller does not disclose the throughput of the clonal selection experiments, Koller demonstrates the throughput of the system in an example where > 105 cells/second are processed and a 0.1% population of unwanted cells are eliminated via photoablation, which corresponds to a photoablation rate of > 100 cells/second (105 cells x 0.1%) (p. 159, 1st full ¶). Koller further teaches that the method can be used to process a wide range of cell contamination levels and plating densities (p. 158, last ¶). It would have thus been obvious for one of ordinary skill in the art to eliminate unwanted cells in a clonal selection method at a rate of at least 60 cells/second with a reasonable expectation of success.
Regarding claim 23, Koller teaches growing the selected clone in the photoablated well (Fig. 5), and it would have been obvious to carry out such methods in multiple wells in parallel in the multiwell plate.

Claims 24 and 25 are rejected under 35 U.S.C. 103 as being unpatentable over the combination of Koller, as applied to claims 21-23, 26 and 40, further in view of Pasparakis et al., Angewandte Chemie International Edition 50.18 (2011): 4142-4145 (cited in IDS of 22 March 2024).
Claims 24 and 25 differ from Koller, as applied to claims 21-23, 26 and 40, in that: the method further comprises photodetaching one or more cells of the clonal population (claim 24); and the method further comprises testing the one or more photodetached cells (claim 25).
Pasparakis teaches a method for photodetaching cultured mammalian cells adhered to a cell culture substrate, comprising coating a substrate with a non-toxic photoresponsive polymer, culturing adherent cells on the coated surface and releasing/detaching the cells by applying a low-energy laser light that photodegrades the polymer (p. 4142, 1st ¶ to p. 4144, 1st full ¶). Cells adhered to the polymer-coated surface in a similar manner as standard tissue culture polystyrene, and the low energy laser allowed for detachment without damage to cells (e.g., DNA damage, heating, free radicals, etc.) (p. 4143, last ¶ to p. 4144, first full ¶). The photodetachment method has the advantage of allowing for gentle release of cells in a spatially controlled manner without need for enzyme or other harsh treatments (p. 4143, last ¶ to p. 4144, first full ¶).
It would have been obvious to one of ordinary skill in the art at the time the invention was made to use the method of Koller to isolate individual cells for clonal expansion using photoablation and to expand the isolated cells wherein the expanded cells are harvested by photodetachment as taught by Pasparakis because it would have been obvious to combine prior art elements according to known methods to yield predictable results. One of ordinary skill would have been motivated to use photodetachment as taught by Pasparakis to harvest the expanded cells because Pasparakis teaches that such harvesting allows for gentle release of cells in a spatially controlled manner without need for enzyme or other harsh treatments. Using photodetachment as taught by Pasparakis to harvest the expanded cells would have led to predictable results with a reasonable expectation of success because Pasparakis teaches that the polymers are non-toxic/biocompatible and the photodegraded products can be readily washed away from harvested cells (p. 4143, last full ¶ to p. 4144, last ¶). Moreover, the method of Koller utilizes laser light for cell isolation and it would have thus been obvious to use similar techniques for the cell harvesting step(s).
Regarding claim 25, Koller teaches that clonal isolation for the purpose of obtaining high-expressing cells, and it would have been obvious to test the clonally expanded cells for the desired property (e.g., to measure expression of the heterologous protein and/or other properties related to such expression, e.g. to determine optimal expression conditions).

Claims 32, 35 and 36 are rejected under 35 U.S.C. 103 as being unpatentable over the combination of Koller, as applied to claims 21-23, 26 and 40, further in view of Koller et al., Protein Engineering For Industrial Biotechnology. CRC Press, 2000. 339-354 (“Koller 2000”).
Claims 32, 35 and 36 differ from Koller, as applied to claims 21-23, 26 and 40, in that: the selecting is based on one or more biomarkers (claim 32); the one or more biomarkers comprise a cell surface receptor (claim 35); and the cell surface receptor is labeled with fluorescently-tagged antibodies that bind specifically to the receptor (claim 36).
Koller 2000 teaches a method of producing recombinant cell surface receptor proteins wherein the expressed proteins are inserted into the host cell membrane with the ligand-binding portion exposed on the cell surface, and high expressing host cells are selected for clonal development by using a fluorescently labeled antibody specific for the recombinant cell surface receptor and selecting based on fluorescence intensity (p. 327, under Isolation of ECD-expressing Cell Lines and Soluble ECDs; Fig. 3; p. 332-334, under Isolation of High Receptor-Expressing Cell Lines).
It would have been obvious to one of ordinary skill in the art at the time the invention was made to use the method of Koller to isolate individual cells for clonal expansion by selecting a desired cell based on fluorescence intensity and using photoablation to eliminate unselected cells wherein the desired cell is selected based on binding of a fluorescently labeled antibody to a cell surface receptor (biomarker) as taught by Koller 2000 because it would have been obvious to combine prior art elements according to known methods to yield predictable results. One of ordinary skill would have been motivated to select clones in the method of Koller using a cell surface receptor/biomarker as taught by Koller 2000 because using the recombinant protein/receptor being expressed by the host cell as a basis for selection would eliminate the need for co-expression of a marker such as GFP and thereby enhance efficiency of the process. Moreover, one of ordinary skill would have been motivated to use the photoablation method of Koller to select clones for expression of the receptors taught by Koller 2000 because Koller teaches that the photoablation method has numerous advantages over traditional FACS based sorting (Koller, p. 154, 1st three full ¶s). Selecting clones in the method of Koller using a cell surface receptor/biomarker as taught by Koller 2000 would have led to predictable results with a reasonable expectation of success because the selection in Koller 2000 is based on the same type of fluorescence intensity parameter as taught by Koller, and
Koller teaches that the photoablation method can be used as an alternative to FACS sorting as taught by Koller 2000 (Koller, p. 154, 1st three full ¶s).

Conclusion
No claim is allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ROBERT J YAMASAKI whose telephone number is (571)270-5467. The examiner can normally be reached M-F 930-6 PST.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Melenie Gordon can be reached on 571-272-8037. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.

/ROBERT J YAMASAKI/Primary Examiner, Art Unit 1657