Damage to the optic nerve in mammals induces retrograde degeneration and apoptosis of the retinal ganglion cell (RGC) bodies. We have previously shown that semaphorins, axon guidance molecules with repulsive cues, are capable of mediating apopto- Damage to the optic nerve in mammals induces retrograde degeneration and apoptosis of the retinal ganglion cell (RGC) bodies. We have previously demonstrated that semaphorins, axon guidance molecules with repulsive cues, are capable of mediating apopto-