Role of the immune system in the maintenance of mouse facial motoneuron viability after nerve injury.

In the field of neuroimmunology, an emerging area of research involves the role that the immune system plays in neural injury and repair. Such immune:neural interactions may involve both neuroprotective and neurodestruction actions. To begin to address the compelling, and clinically relevant, issue of how the immune system impacts neural reparative processes, we combined the well described facial nerve injury paradigm, a simple neural injury model, with various immunodeficient mouse models, in order to delineate the contributing immune cells/factors involved in neural injury and repair. We have discovered a role for the CD4+ T cell in mediating facial motoneuron survival after facial nerve injury in the mouse. In this review, we present an overview of our work to date in this field and discuss future directions relevant to understanding key elements in the crosstalk between the immune:neural systems that develops subsequent to injury and/or trauma.