I am trying to synchronize Raji cells which are suspended cells. But after 24 h of serum starvation they attached to the flask. Does anyone know why they are doing so and how can that be prevented?
Sodium Butyrate, which causes G0/G1 arrest in Raji cells, has the same effect. See attached paper. The morphological change is distinct. Be careful when you re-stimulate the cells as you can easily induce apoptosis - reduce the time of starvation to one that gives you the least cell death.
If you try to prevent it, you will also get apoptosis!!
I am not an expert on Raji cells, but for sure serum starvation induces a G0/G1 block in their cell cycle. From the adhesion point of view, G1 phase is characterized by a general increase in the formation of Focal Adhesions after mitotic detachment and rounding. Thus, this could be the reason for the increased adhesion to the substrate. I think you could use trypsin to detach them (as routinely done to split epithelial cell lines), or you can starve them in no-adhesive conditions. For instance, you could use poly-Hema to coat the flask and avoid cell attachment.