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CRL-1573 culture conditions and cell density
What are the recommended culture conditions and cell density for ATCC® CRL-1573 ™, HEK-293 cells?

It is not unusual for CRL-1573 cells to detach and float.  If allowed to sit at room temperature too long, the cells will detach from the flasks. This can even include incubating the cells in flasks placed too close to the door of an incubator that is accessed frequently or if the monolayer gets over confluent.  This is normal for these cells, the floating cells will re-attach to the flask over a period of several days in culture at 37°C and should not be discarded.  When refreshing the medium, pipette the fresh medium gently along the walls of the flask and not directly over the cells, all floating cells should be retained (by gentle centrifugation) and added back to the same flask with the adherent population. 

The cell density is important to properly maintain these cells. CRL-1573 may be initiated at a density of 2 x 104 to 4 x 104 cells/cm2.   Cell counts are important to ensure that they maintain the proper cell density and the cells should be subcultured weekly when the density is between 6 x 104 and 7 x 104 cells/cm2.   Cultures initiated into a T75 flask typically require 5 days in culture before they can be transferred into a T-225.  Growth will be patchy for the first few days but will soon form an adherent monolayer of epithelial cells

Date Created02/21/2014 11:05 AM
Date Updated04/07/2014 08:49 AM

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