Following our step-by-step banking best practices not only will safeguard your material in case of early contamination but will also ensure consistency within your material. 

  • Following derivation, as early as possible, seed vials are banked to safeguard the materials in case of early contamination. These seed materials would only be used in case of loss of the initial culture or the creation of additional master cell banks if necessary.
  • A Master Cell Bank (MCB) is created. A portion of the master cell bank should be stored off-site to safeguard in case of catastrophic loss. 
  • The MCB is used to create second tier Working Cell Bank (WCB). 

Use of a two-tiered banking strategy enables consistency within the WCBs, as they will all be created from the same bank of materials, and therefore available at approximately the same passage over time.  It also allows for staged testing and characterization, which can result in well characterized banks at a significant cost savings.  Testing can be staged so that certain tests, like bloodborne pathogen testing, can be performed on the MCB, and may not need to be repeated on each WCB generated from that MCB.
Two-Tiered Banking Strategy


 A cell bank is created from a single culture, pooled before cryopreservation, frozen on the same day, by the same technical team (ideally a single technician). This strategy creates a homogenous bank of material which allows any testing done on a single vial to be representative of the entire bank.  For this reason, pooling of materials is critical in generating both MCBs and WCBs for use.

Creating a cell lot



 We recommend a tiered testing scheme. 

Where possible, Short Tandem Repeat (STR) testing should be done on donor material. If that is not possible then testing should be performed on early primary material or seed stocks. This first STR result establishes the genetic identity of the material and must be done as early as possible. Once established, this genetic fingerprint can be used to authenticate the cell line over time.
  • Tier 1 Bank Tests performed on the MCB one time.
  • Tier 2 Bank Tests performed on each WCB created from the MCB.   
  • Additional testing may be performed on the MCB or WCB based on your specific research goals and specific needs. Examples include confirmation of gene edits and assessment of off-target changes, presence of reporters, etc. 
Recommended Chracterization Testing Scheme