Cell lines that have been frozen for more than five years have a known history of instability or are of undetermined status, should be subcloned prior to being used for production. Our catalog number 99900400 is a process in which the cell line is subcloned twice by limiting dilution.
At the end of this process a determination will be made as to whether the cell line exhibits stable antibody secretion. Subclones are also screened for growth rate and amount of antibody produced. There are many instances where a hybridoma will have a 100% secretion rate and will not require more than two subclonings. At this point a subclone exhibiting a high growth rate and superior antibody production will be selected for cryopreservation and further cell banking. Cell lines that do not meet the 100% criteria will have a small freezer lot prepared in order to preserve the subcloning work already done. In order to stabilize the cell line and make it production ready, it must be put through a more extensive cloning process.