As used at work, doesn't refer to recovering from an illness or traumatic event. Instead it refers to the purification of protein from the fermentation broth in which it was produced. Usually accomplished by several sequential chromatography steps and possibly a UFDF (ultrafiltration-diafiltration) step.
For instance, if the production process involves bacterial cells such as E. coli, the target protein must be separated out from everything else in the fermentation broth, which would include E.coli proteins, DNA, and endotoxin. Any of these impurities, if not eliminated from the final drug product, could trigger a HAHA response, or worse, if injected into a patient.