The ephrin subclasses A and B are not thought to interact much with each other's receptors. A study in this issue now shows that ephrin-A5 can signal through the EphB2 receptor, toppling this dogma.
The use of annexin A5 (A5) and either propidium iodide or 7-aminoactinomycin D (PI/7-AAD) stains to measure cell death by flow cytometry has been considered the gold standard by most investigators.