U937 monocyte suspension culture adhering to flask. Why?!

[Stephen R. Lasky, Ph.D. alt.binaries.pictures.erotica.blondes alt.binaries.pictures.erotica.d alt.binaries.pictures.erotica.female alt.binaries.pictures.erotica.male alt.binaries.pictures.erotica.orientals alt.binaries.pictures.fine-art.d alt]

In article <39vjpt$ekm at mserv1.dl.ac.uk>, psansom at hgmp.mrc.ac.uk (Mr. P.A.
Sansom) wrote:

> OK, to set the scene
> Little me growing U937 monocytic cell line in
>     RPMI 1640
> with
>     2mM L-glutamine
>     5% heat inactivated fetal calf serum
>     5% CO2 humidified
> in
>     Falcon tissue culture flasks (plastics)
> 
> Problem is that they have started adhering to the plastic of the flask, making
> it hard to harvest them as intact cells for my expts

Paul, in my experience U937's become adherent when they begin to
differentiate into monocyte like cells.  I do this on purpose to study the
effects of vitamin D3.  Also happens with TPA, DMSO, RA and other agents
(although not necessarily towards monocytes).  I have also seen this
happen in U937, HL60 and CML cell cultures that have been carried for a
long time.  Maybe defrosting a new vial of U937's would solve the problem.

SRLasky

-- 
*********************************************************************Stephen R. Lasky, Ph.D.
Roger Williams Medical Center/Brown University
Phone: 401-456-6572       Fax: 401-456-6569       e-mail: Stephen_Lasky at brown.edu
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"To me at least, 'Yuck' doesn't capture the full essence of death by
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