MVs activate human bone marrow stromal cells. (A) MVs isolated from different CLL patients' plasma exhibiting variable degrees of AKT activation in HS-5 cell line as determined by densitometric analysis of the results from Western blot. (B-D) MVs activate primary BMSCs isolated from CLL or healthy human subjects as analyzed by Western blot. A sustained level of AKT activation is detected at least up to 24 hours after incubation with MVs.