Hi, I am using BD's CD44-PE (IM7 clone) at 1:200 (recommended 1:50) with PBS/2% FBS 1mM EDTA and appear to have a high background with MCF7 cells. Ab incubation 15min on ice. Anybody have suggestions?

Thanks

You could try blocking with mouse serum as a source of unlabeled antibody.

Are you using Fc block of some kind (FBS won't do)?