Can I skip the FC blocking step in flow cytometry? - (Feb/03/2015 )

Can I skip the FC blocking step in flow cytometry?  and when I shouldn't do that?

You can skip it but it might lead to a higher background. I wouldn't do it when staining macrophages or monocytes since they have a lot of Fc receptors

As Tab said, however, you can do away this step if you are staining whole blood (because there is a lot of serum in the whole blood blocking the Fc receptors).

what about staining a monolayer cell line not blood ?