Cells for producing influenza virus and method for producing influenza virus
Inventors
Kawaoka, Yoshihiro • Watanabe, Tokiko • KAWAKAMI, Eiryo • Watanabe, Shinji
Assignees
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-11964009-B2
Publication Date
2024-04-23
Expiration Date
Abstract
The present invention provides cells which have a high ability to propagate influenza virus, are suitable for use in production of an influenza virus for preparing a vaccine, and are able to be cultured in vitro, and a method for producing an influenza virus using the cells. That is, the present invention provides cells for producing an influenza virus in which expression of one or more genes that encode proteins involved in an effect of suppressing influenza virus production in a cell is suppressed and the gene is at least one selected from the group including ACTG1 gene and the like, and a method for producing an influenza virus that includes infecting the cells for producing an influenza virus with an influenza virus and then culturing.
Core Innovation
The invention relates to influenza virus vaccine-production cells in which expression of flu propagation suppressing genes is suppressed, deleted, or disrupted, where the suppressed genes are flu propagation suppressing genes that promote viral propagation when suppressed. The document describes engineered influenza virus vaccine-production cells that are able to be cultured in vitro and in which influenza virus is produced after infection.
A gene set for suppressing gene expression is provided, and the document identifies specific genes including ACTG1 and TMED2. The document further describes quantitative preferred knockdown levels for suppressed expression, including reduction to 50% or less.
The document supports the engineered-cell concept with described experimental evidence involving identification of host proteins interacting with influenza proteins, RNAi knockdown screening in HEK293 showing improved virus titers with adequate cell viability, follow-up responsive gene sets in Vero and MDCK including ACTG1 and TMED2, and gene disruption in MDCK showing increased virus titers for KRT18 and USP10 clones.
Claims Coverage
Two independent claims are directed to cells for producing influenza virus in which expression of TMED2 gene is suppressed, with each independent claim specifying a cell type: Vero or MDCK for one claim, and HEK293 for the other. Across the independent claims, the number of inventive features is two: the specific host cell type, and suppression of TMED2 gene expression in cells that are able to be cultured in vitro and infected with influenza virus.
Vero or MDCK cells with suppressed TMED2 for influenza virus production
Cells for producing an influenza virus that are Vero cells or MDCK cells in which expression of TMED2 gene is suppressed, wherein the cells are able to be cultured in vitro and are infected with influenza virus.
HEK293 cells with suppressed TMED2 for influenza virus production
Cells for producing an influenza virus that are HEK293 cells in which expression of TMED2 gene is suppressed, wherein the cells are able to be cultured in vitro and are infected with influenza virus.
The claims primarily cover influenza virus production using in vitro culturable Vero or MDCK cells and HEK293 cells, respectively, where TMED2 gene expression is suppressed, and the cells are infected with influenza virus. Dependent claims further specify a preferred suppression level of TMED2 expression reduced to 50% or less relative to the same cell type before suppression.
Stated Advantages
Improved virus titers, while maintaining adequate cell viability, is described based on knockdown screening results in the document.
Documented Applications
Producing an influenza virus, including influenza virus vaccine-production, by infecting engineered, in vitro-cultured cells in which TMED2 gene expression is suppressed and collecting secreted virus.
Interested in licensing this patent?