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TIB-71 growth and morphology

What is the normal growth and morphology for ATCC® TIB-71 ™, RAW 264.7 cells?

TIB-71 is a monocyte/macrophage cell line that will have both loosely adherent cuboidal or spindle-shaped cells and rounded viable cells.  It is normal for the cells to be loosely attached and pile and become rounded, especially when the culture is dense.  Viable cells can detach and float, especially as the culture becomes more confluent.  These unattached cells are still viable and should be retained by gentle centrifugation then added back to the flask.  Slight variations in different lots of serum can cause more or less attachment of RAW 264.7 cells.  We use high quality serum (ATCC® 30-2020 ™) that has not been heat-inactivated, since heat-inactivation can reduce the attachment factors and growth factors.


When subculturing TIB-71 it is important to leave 10 ml of medium in a T75 flask (4 or 5 ml in a T25) before scraping.  When using the scraper to dislodge the cells she should be careful to make only one pass through the flask, from the bottom to the top, to avoid damaging the cells.  It is normal for viability to drop after subculturing by scraping and the cells may need longer to attach to the new flasks. 

Date Created02/21/2014 11:34 AM
Date Updated02/21/2014 11:35 AM

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