THP-1 differentiated cells detach when washing with PBS (Mg and Ca free PBS) - (Dec/07/2012 )

Hello there,
i am relatively new to THP-1 cell culture. I have succeeded to differentiate my THP-1 to adherent cells. these differentiated cells will be used for a toxicological study. however, if i remove the medium and wash the cells with warm PBS, even the control cells (non treated) do detach to a certain extent. does anyone have an idea how to circumvent this problem? precoating the 96WP with poly-d-lysine?
thanks in advance for your help!
best,
wurmbox

Try washing by PBS containing Mg and Ca.
If It does not solve the problem, you should try new stock cell or buy new one from ATCC or German culture collection ( www.dsmz.de ) or European culture collections ( www.hpacultures.org.uk/collections/ecacc.jsp ).

Base on my experience, this shows that THP-1 is not in a good mood.

Dear memari,
thanks a lot for your answer. i was trying them with different conditions and it turned out that i probably seeded them, when they were already too "dense", i.e. too confluent. now it worked, they can even bear 1%DMSO.
best to all!
wurmbox