WARF: P100246US02

  • Assigned to WARF as biological material.

Influenza Variant Grows Well in CHO Cells


Yoshihiro Kawaoka, Makoto Ozawa

The Wisconsin Alumni Research Foundation (WARF) is seeking commercial partners interested in developing a modified PR8 influenza virus that efficiently replicates in Chinese Hamster Ovary cells.
OVERVIEWVaccines against influenza and other viruses can be grown in Chinese Hamster Ovary (CHO) cells. Problematically, an influenza virus that is made by combining H1N1 and PR8 strains, and that is recommended by the World Health Organization as a donor strain to produce yearly vaccines, does not replicate well in CHO cells.
THE INVENTIONUW–Madison researchers have developed a modified version of the PR8 virus to grow in high yields in CHO cells. The modified strain could be used as the donor ‘backbone’ in the annual influenza vaccine. The backbone combines six gene segments encoding ‘internal’ viral products with gene variants for the two cell surface proteins (NA and HA) that characterize a given year’s influenza threat.
  • Producing CHO cell-adapted PR8 influenza virus
  • Replicates in CHO cells 10 times more efficiently
Contact Information
For current licensing status, please contact Jennifer Gottwald at or 608-960-9854.
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