COS-7

COS-7 cells are a fibroblast-like cell line derived from African green monkey kidney tissue and are a vital resource in research, particularly for their high transfection efficiency, making them a popular choice for the expression of recombinant proteins. COS-7 cells are derived from the CV-1 cell line and transformed with a mutant form of the simian virus 40 (SV40), which includes a replication origin that allows for episomal replication of transfected plasmids containing the SV40 origin of replication.

Transfection of COS-7 cells is facilitated by transfection reagents such as Lipofectamine, with an efficiency that mirrors those observed in HeLa cells. Conventional methods can achieve up to 80% transfection efficiency in COS-7 cells, showcasing their ease of genetic manipulation. The ability of COS-7 cells to accommodate large plasmids and replicate them, leading to high yields of the desired recombinant proteins, make them an invaluable resource for various applications, including gene expression studies, signal transduction pathway investigations, and the production of proteins for biochemical analyses.

COS-7 cells exhibit a strong susceptibility to various viruses, making them an excellent model for virology studies, including virus-host interaction investigations, viral life cycle elucidation, and antiviral drug testing. Their permissiveness to viral entry and replication is leveraged to study the mechanisms of viral infection, pathogenesis, and the cellular responses elicited by viral invaders. Consequently, COS-7 cells serve as a valuable tool in the development of viral vectors for gene therapy and vaccine research.

COS-7 cells are a cornerstone in research due to their high transfection efficiency and utility in recombinant protein expression. Their ease of genetic manipulation, combined with susceptibility to viruses, makes them indispensable for studies in gene expression, signal transduction, virology, and the development of viral vectors, solidifying their role as a versatile tool in both basic and applied biological sciences.

37°C, 5% CO₂, humidified atmosphere.

1. Confirm that the vial remains deeply frozen upon delivery, as cells are shipped on dry ice to maintain optimal temperatures during transit.

2. Upon receipt, either store the cryovial immediately at temperatures below -150°C to ensure the preservation of cellular integrity, or proceed to step 3 if immediate culturing is required.

3. For immediate culturing, swiftly thaw the vial by immersing it in a 37°C water bath with clean water and an antimicrobial agent, agitating gently for 40-60 seconds until a small ice clump remains.

4. Perform all subsequent steps under sterile conditions in a flow hood, disinfecting the cryovial with 70% ethanol before opening.

5. Carefully open the disinfected vial and transfer the cell suspension into a 15 ml centrifuge tube containing 8 ml of room-temperature culture medium, mixing gently.

6. Centrifuge the mixture at 300 x g for 3 minutes to separate the cells and carefully discard the supernatant containing residual freezing medium.

7. Gently resuspend the cell pellet in 10 ml of fresh culture medium. For adherent cells, divide the suspension between two T25 culture flasks; for suspension cultures, transfer all the medium into one T25 flask to promote effective cell interaction and growth.

8. Adhere to established subculture protocols for continued growth and maintenance of the cell line, ensuring reliable experimental outcomes.

Mycoplasma contamination is excluded using both PCR-based assays and luminescence-based mycoplasma detection methods.

To ensure there is no bacterial, fungal, or yeast contamination, cell cultures are subjected to daily visual inspections.

For long-term preservation, place vials in vapor-phase liquid nitrogen at about −150 to −196 °C. Storage at −80 °C is acceptable only as a short interim step before transfer to liquid nitrogen.

Cryopreserved cell lines are shipped on dry ice in validated, insulated packaging with sufficient refrigerant to maintain approximately −78 °C throughout transit. On receipt, inspect the container immediately and transfer vials without delay to appropriate storage.

At Cytion, we stand behind the quality and viability of our products. We guarantee that our cells will be viable at the start of culture for 60 days after shipment from our facilities. We assure that all materials conform to the specifications described in the Certificate of Analysis and/or Product Sheet.

For full details, please refer to our Warranty Statement.