Resuscitating frozen cells

In the event of cell cultures becoming contaminated with bacteria, fungi or mycoplasmas, the best course of action is to discard the culture, check cell culture reagents for contamination, thoroughly disinfect all safety cabinets and work surfaces and resuscitate a fresh culture from previously frozen stock. In the case of contamination with a spore-forming organism, and where such facilities exist, room fumigation may also be advisable. 

Resuscitation and enrichment methods Some bacteria and fungi that have been frozen, dried, suble-thally heated, or exposed to chemical inhibitors may suffer sublethal damage and not replicate when placed on growth media, especially media that contain selective inhibitors. If these cells are not allowed to resuscitate, under-counts may result and, in the case of pathogens, a product may be declared pathogen-free when in fact it is not. 

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