DG44

Research purposes, Transfection suitable, Protein production

DHFR -(deficient), genome at: https://chogenome.org

DG44 is a CHO derivative which is dihydrofolate reductase (DHFR)- deficient, Both alleles of the dhfr gene have been deleted. Growth of this cell line requires a source of purines and thymidine.

DG44 was derived in several steps from CHO pro3- cells. This cell line is useful for selection of transgenes of interest linked to a dhfr minigene using standard growth media that lack a source of purines and/or thymidine and therefore these cells do not require antibiotic resistance selection.

The base medium for this cell line is HyClone™ MEM Alpha Modificationwith with nucleosides and deoxynucleosides (Cytiva catalog # SH30265.01). To make the complete growth medium, add the following components to the base medium:

• Fetal bovine serum (FBS; ATCC 30-2020) to a final concentration of 10% 

1. Remove and discard culture medium.
2. Briefly rinse the cell layer with PBS (ATCC catalog # 30-2200) to remove all traces of serum that contains trypsin inhibitor.
3. Add 2.0 to 3.0 mL of Trypsin-EDTA for Primary Cells (ATCC catalog # PCS-999-003) solution to flask and observe cells under an inverted microscope until cell layer is dispersed (usually within 5 to 15 minutes).
   Note: To avoid clumping do not agitate the cells by hitting or shaking the flask while waiting for the cells to detach. Cells that are difficult to detach may be placed at 37°C to facilitate dispersal.
4. Add 6.0 to 8.0 mL of complete growth medium and aspirate cells by gently pipetting.
5. Centrifuge cell suspension at 150 to 200 xg for 8 to 12 minutes to remove dissociation agent.
6. Discard supernatant and resuspend cell pellet in fresh complete culture media.
7. Add appropriate aliquots of the cell suspension to new culture vessels.
   Cultures can be established between 1.0 x 10⁴ and 3.0 x 10⁴ viable cells/cm².
8. Incubate cultures at 37°C.

1. Remove and discard culture medium.
2. Briefly rinse the cell layer with PBS (ATCC catalog # 30-2200) to remove all traces of serum that contains trypsin inhibitor.
3. Add 2.0 to 3.0 mL of Trypsin-EDTA for Primary Cells (ATCC catalog # PCS-999-003) solution to flask and observe cells under an inverted microscope until cell layer is dispersed (usually within 5 to 15 minutes).
   Note: To avoid clumping do not agitate the cells by hitting or shaking the flask while waiting for the cells to detach. Cells that are difficult to detach may be placed at 37°C to facilitate dispersal.
4. Add 6.0 to 8.0 mL of complete growth medium and aspirate cells by gently pipetting.
5. Centrifuge cell suspension at 150 to 200 xg for 8 to 12 minutes to remove dissociation agent.
6. Discard supernatant and resuspend cell pellet in fresh complete culture media.
7. Add appropriate aliquots of the cell suspension to new culture vessels.
   Cultures can be established between 1.0 x 10⁴ and 3.0 x 10⁴ viable cells/cm².
8. Incubate cultures at 37°C.

Complete Culture Medium + 5% DMSO

The product is provided 'AS IS' and the viability of ATCC^® products is warranted for 30 days from the date of shipment, provided that the customer has stored and handled the product according to the information included on the product information sheet, website, and Certificate of Analysis. For living cultures, ATCC lists the media formulation and reagents that have been found to be effective for the product. While other unspecified media and reagents may also produce satisfactory results, a change in the ATCC and/or depositor-recommended protocols may affect the recovery, growth, and/or function of the product. If an alternative medium formulation or reagent is used, the ATCC warranty for viability is no longer valid.  Except as expressly set forth herein, no other warranties of any kind are provided, express or implied, including, but not limited to, any implied warranties of merchantability, fitness for a particular purpose, manufacture according to cGMP standards, typicality, safety, accuracy, and/or noninfringement.

This product is intended for laboratory research use only. It is not intended for any animal or human therapeutic use, any human or animal consumption, or any diagnostic use. Any proposed commercial use is prohibited without a license from ATCC.

While ATCC uses reasonable efforts to include accurate and up-to-date information on this product sheet, ATCC makes no warranties or representations as to its accuracy. Citations from scientific literature and patents are provided for informational purposes only. ATCC does not warrant that such information has been confirmed to be accurate or complete and the customer bears the sole responsibility of confirming the accuracy and completeness of any such information.

This product is sent on the condition that the customer is responsible for and assumes all risk and responsibility in connection with the receipt, handling, storage, disposal, and use of the ATCC product including without limitation taking all appropriate safety and handling precautions to minimize health or environmental risk. As a condition of receiving the material, the customer agrees that any activity undertaken with the ATCC product and any progeny or modifications will be conducted in compliance with all applicable laws, regulations, and guidelines. This product is provided 'AS IS' with no representations or warranties whatsoever except as expressly set forth herein and in no event shall ATCC, its parents, subsidiaries, directors, officers, agents, employees, assigns, successors, and affiliates be liable for indirect, special, incidental, or consequential damages of any kind in connection with or arising out of the customer's use of the product. While reasonable effort is made to ensure authenticity and reliability of materials on deposit, ATCC is not liable for damages arising from the misidentification or misrepresentation of such materials.

Please see the material transfer agreement (MTA) for further details regarding the use of this product. The MTA is available at www.atcc.org.