Eph/ephrin signaling as a potential therapeutic target after central nervous system injury.

Recent work indicates that the expression of Eph and ephrin proteins is upregulated after injury in the central nervous system (CNS). Although to date, much of the interest in these protein families in the nervous system has been on their roles during development, their presence in the adult CNS at multiple time points after injury suggest that they play significant roles in key aspects of the nervous system's response to damage. Several fundamental features of Eph and ephrin biology, such as bidirectional signaling, promiscuity of ligand-receptor binding, and potential cis regulation of function, present challenges for the formulation of rational and effective Eph/ephrin based strategies for CNS axon regeneration. However, recent work that have identified specific functions for individual Ephs and ephrins in injury-induced phenomena such as axon sprouting, cellular remodeling, and scar formation has begun to tease apart their contributions and may provide a number of potential entry points for beneficial therapeutic intervention.