# US 2021/0340501 A1 · Methods to Control Viral Infection in Mammalian Cells > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0340501 A1 - Document ID: US20210340501A1 - Status: Published application - Kind: A1 - Application number: 17/270,501 - Filed: 2019-08-27 - Published: 2021-11-04 - Earliest claimed: 2018-08-27 - Assignees: The Regents of the University of California; Food and Drug Administration - Applicants: The Regents of the University of California; The Food and Drug Administration - Inventors: Nathan Lewis; Wan-Tien Chiang; Montserrat Puig; Yaqin Zhang; Amy Rosenberg - Web page: https://patentgrep.com/patent/US20210340501A1 ## CPC - C12N 5/0682: {Cells of the female genital tract, e.g. endometrium; Non-germinal cells from ovaries, e.g. ovarian follicle cells (oocytes C12N5/0609)} - C12N 15/117: Nucleic acids having immunomodulatory properties, e.g. containing CpG-motifs - A61P 31/12: Antivirals - C12N 15/113: Non-coding nucleic acids modulating the expression of genes, e.g. antisense oligonucleotides; {Antisense DNA or RNA; Triplex- forming oligonucleotides; Catalytic nucleic acids, e.g. ribozymes; Nucleic acids used in co-suppression or gene silencing (when used in plants C12N15/8218)} - C12N 2310/17: Immunomodulatory nucleic acids - C12N 2310/20: involving clustered regularly interspaced short palindromic repeats [CRISPR] - C12N 2320/31: Combination therapy - C12N 2501/24: Interferons [IFN] - C12N 2501/50: Cell markers; Cell surface determinants - C12N 2501/90: Polysaccharides - C12N 2501/998: Proteins not provided for elsewhere - C12N 2501/999: Small molecules not provided for elsewhere - C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00) - A61P: SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS ## Abstract A significant interferon (IFN) response is induced following treatment of CHO cells with exogenously-added type I IFN or poly I:C. Treatment of the CHO cells with poly I:C prior to infection limited the cytopathic effect from Vesicular stomatitis virus (VSV), Encephalomyocarditis vims (EMCV), and Reovirus-3 vims (Reo) in a STAT1-dependent manner By knocking out two upstream repressors of STAT1: Gfi1 and Trim 24, the engineered CHO cells exhibited increased resistance to virus contaminations. Thus, omics-guided engineering of mammalian cell culture can be deployed to increase safety in biotherapeutic protein production. ## Claims ### Claim 1 A method of inhibiting viral infection in a biological sample comprising administering to the sample an effective amount of: a) a type I interferon or poly I:C; b) a compound activating an innate immune response in the sample; c) a compound suppressing expression of Gfi1, Trim24 and/or Cb1 in the sample; and/or d) a compound activating expression of IRF7, IRF3, STAT1, STAT3, NFATC2, IRF5, STAT4, IRF9, IRF8, NFKB1, TP53, JUN and/or EBF1 in the sample. ### Claim 2 (depends on 1) The method of claim 1, wherein the biological sample is a cell culture. ### Claim 3 (depends on 1) The method of claim 1, wherein the biological sample comprises mammalian cells. ### Claim 4 (depends on 1) The method of claim 1, wherein the biological sample comprises CHO cells. ### Claim 5 (depends on 1) The method of claim 1, wherein the method is conducted in a biopharmaceutical manufacturing process. ### Claim 6 (depends on 1) The method of claim 1, wherein the compound suppresses expression of Gfi1, Trim24 and/or Cb1 in the sample. ### Claim 7 (depends on 1) The method of claim 1, wherein the compound activates expression of IRF7, IRF3, STAT1, STAT3, NFATC2, IRF5, STAT4, IRF9, IRF8, NFKB1, TP53, JUN and/or EBF1 in the sample. ### Claim 8 (depends on 1) The method of claim 1, wherein the virus is VSV, EMCV REO, an RNA virus, or a DNA virus. ### Claim 9 (depends on 1) The method of claim 1, wherein the compound is a nucleic acid. ### Claim 10 A non-naturally occurring mammalian cell culture comprising cells genetically modified for suppressed expression of Gfi1, Trim24 and/or Cb1, and/or activated expression of IRF7, IRF3, STAT1, STAT3, NFATC2, IRF5, STAT4, IRF9, IRF8, NFKB1, TP53, JUN and/or EBF1, as compared to wild-type cells of the same mammalian species. ### Claim 11 A method of producing a biopharmaceutical protein from a mammalian cell culture, comprising culturing mammalian cells having non-naturally occurring genetically suppressed expression of Gfi1, Trim24 and/or Cb1, and/or genetically activated expression of IRF7, IRF3, STAT1, STAT3, NFATC2, IRF5, STAT4, IRF9, IRF8, NFKB1, TP53, JUN and/or EBF1, as compared to wild-type cells of the same mammalian species; and isolating a protein of interest from the cultured cells. ### Claim 12 (depends on 11) The method of claim 11, wherein the biological sample comprises CHO cells. ### Claim 13 (depends on 11) The method of claim 11, wherein the cells have suppressed expression of Gfi1, Trim24 and/or Cb1. ### Claim 14 (depends on 11) The method of claim 11, wherein the cells have activated expression of IRF7, IRF3, STAT1, STAT3, NFATC2, IRF5, STAT4, IRF9, IRF8, NFKB1, TP53, JUN and/or EBF1. ### Claim 15 A method of treating or preventing viral infection in a mammalian cell comprising administering to the cell an effective amount of: a) a type I interferon or poly I:C; b) a compound activating an innate immune response in the sample; c) a compound suppressing expression of Gfi1, Trim24 or Cb1 in the sample; and/or d) a compound activating expression of IRF7, IRF3, STAT1, STAT3, NFATC2, IRF5, STAT4, IRF9, IRF8, NFKB1, TP53, JUN and/or EBF1 in the sample. ### Claim 16 A method for increasing virus infectivity in a mammalian cell comprising increasing expression of Gfi1, Trim24 or Cb1, and/or decreasing expression of IRF7, IRF3, STAT1, STAT3, NFATC2, IRF5, STAT4, IRF9, IRF8, NFKB1, TP53, JUN and/or EBF1 in the cell. ### Claim 17 (depends on 16) The method of claim 16, wherein the method further comprises isolating virus or viral particles from the cell. ### Claim 18 (depends on 16) The method of claim 16, wherein genetic material is delivered to the sample by viral transduction to increase or decrease expression of said gene. ### Claim 19 A non-naturally occurring mammalian cell culture comprising mammalian cells having genetically activated expression of Gfi1, Trim24 or Cb1, and/or genetically suppressed expression of IRF7, IRF3, STAT1, STAT3, NFATC2, IRF5, STAT4, IRF9, IRF8, NFKB1, TP53, JUN and/or EBF1, as compared to wild-type cells of the same mammalian species. ### Claim 20 A mammalian cell modified for in vivo suppressed expression or activity of Gfi1, Trim24 and/or Cb1, and/or activated expression or activity of IRF7, IRF3, STAT1, STAT3, NFATC2, IRF5, STAT4, IRF9, IRF8, NFKB1, TP53, JUN and/or EBF1, as compared to wild-type cells of the same mammalian species.