With our partners at Cytivia (who host Prof Gibson as a Royal Society Industry fellow) and the Sagona Group (School of life sciences) we have investigated how polymers can be used to cryopreserve bacteriophages. Methods to freeze cells have attracted huge interest of late, for application in cell based therapies and biotechnology.We have, for example, developed macromolecular cryoprotectants which can control ice growth/formation and/or protect cells during freezing. However, virus storage is less explored. Viruses are essential from as vaccines, to vectors to engineer cells. Bacteriophages (phage) are specific bacterial viruses and several are used already to remove bacterial infections and they may have application in the future as therapies, or diagnostics. In this work, we observed (surprisingly) that just adding a small amount of PEG (poly(ethyleneglycol) protected phage during several freeze/thaw cycles at both -80 and -20 C. The mechanism of this was not clear, but ice growth (and its inhibition) was ruled out. We are continuing to study this, and to evaluate the use of polymers in many cryopreservation scenarios.

Read the paper here

Polymer Mediated Cryopreservation of Bacteriophages