21.3.1 Preparation of Cell Banks
Vero cells (ATCC CCL81.4) are maintained for four passages in SFM for cell adaptation to this medium. The cells are amplified through subcultures in TC-flasks using animal origin-free trypsin-like enzyme, and SFM. Vero cells from these flasks were used to prepare the Master Cell Bank (MCB). The cell suspension is distributed in cryogenic vials with 6–8×106 cells/vial and stored overnight at−80°C, and subsequently in liquid nitrogen. Vials from this bank are taken for quality control tests and the MCB is considered certified only after it passed such tests.12
One vial from the MCB is thawed, and the cells are expanded in TC-flasks using SFM and animal origin free-trypsin to obtain the Vero cell suspension needed for the Working Cell Bank (WCB). The WCB are prepared according to procedures described for the MCB and certified with the same tests.12
