Methods to study and distinguish necroptosis

During the decade the importance of regulated necrotic cell death in several pathologies has been increasingly recognized. Intensified research has uncovered many pathways involved in regulated necrosis (RN) that has resulted in several neologisms. The best characterized form of RN is induced by receptor-interacting protein kinase-1 and -3, coined as necroptosis. Unfortunately, until now there are no positive and distinguishing markers available for any of these forms of regulated necrosis, let alone a single marker that identifies regulated necrosis from apoptosis. Here we present an overview of different methods that can be used to discriminate apoptosis from necrosis, more in particular necroptosis, both in vivo and in vitro. Methods for necrotic cell death detection are summarized, and potential pitfalls of these methods are briefly discussed. Basically, a sequential approach is proposed to determine the cell death modality by following a decision tree, allowing discrimination between apoptosis and different forms of RN. Finally, pharmacological and transgenic methods for dissecting subroutines in RN are mentioned