Gibco™ 293-F cells were cloned from the original 293 cell line and adapted to Gibco™ CD 293 Medium. The 293 cell line is a permanent line established from primary embryonic human kidney and transformed with sheared human adenovirus type 5 DNA. The E1A adenovirus gene is expressed in these cells and participates in transactivation of some viral promoters, allowing these cells to produce very high levels of protein. Gibco™ 293-F cells in Gibco™ CD 293 Medium feature:
• Quick thaw into suspension culture directly in Gibco™ CD 293 Medium or Gibco™ 293 SFM II
• Faster growth, superior transfection efficiencies and high protein expression levels
• Documented lineage from a low passage Master Cell Bank
• Quality and performance testing

Quick thaw into suspension culture directly in Gibco™ CD 293 Medium or Gibco™ 293 SFM II
Each vial containing 7.5 × 10⁶ cells can be thawed directly into suspension culture in either Gibco™ CD 293 Medium or Gibco™ 293 SFM II supplemented with 4 mM L-glutamine or GlutaMAX™ reagent. Protocols are provided in the product manual.

Faster growth, superior transfection efficiencies and high protein expression levels
Gibco™ 293-F cells were prepared from a clone selected for fast growth in serum-free medium, superior transfection efficiencies and a high level of protein expression. Optimal transfection efficiencies are obtained with Lipofectamine™ 2000 or 293fectin™ transfection reagents.

Documented lineage from a low passage Master Cell Bank
The parental 293 cells were cloned by limiting dilution; the clone selected exhibited fast growth and high transfection efficiency. This clone was then re-cloned by limiting dilution; of these clones, the 293-F clone was then selected for its fast growth in serum free medium. The serum-free Master Cell Banks were prepared at approximately passage 25.

Quality and performance testing
Each lot of Gibco™ 293-F cells is tested for cell growth and viability post-recovery from cryopreservation. In addition, the Master Seed Bank has been tested for contamination of bacteria, yeast, mycoplasma and virus and has been characterized by isozyme and karyotype analysis.

Product Use
For Research Use Only. Not for any animal or human therapeutic or diagnostic use. Caution: Handle as potentially biohazardous material under at least Biosafety Level 2 containment. This product contains Dimethyl Sulfoxide (DMSO), a hazardous material. Review the Material Safety Data Sheet before handling.