A subtype of T cells impedes tissue repair in aged spinal cord after injury.

In this issue of Neuron, Kong et al. identify targetable natural killer-like T cells that seed the intact aged human and murine spinal cords and increase further after injury. These cells impede myeloid-cell-dependent wound healing in the aged injured cord through expressing natural killer cell granule protein 7 (NKG7).

Functional optic tract rewiring via subtype- and target-specific axonal regeneration and presynaptic activity enhancement.

Mechanisms underlying functional axonal rewiring after adult mammalian central nervous system (CNS) injuries remain unclear partially due to limited models. Here we develop a mouse intracranial pre-olivary pretectal nucleus (OPN) optic tract injury model and demonstrate that Pten/Socs3 knockout and CNTF expression in retinal ganglion cells (RGCs) promotes optic tract regeneration and OPN reinnervation. Revealed by transmission electron microscopy, trans-synaptic labeling, and electrophysiology, functional synapses are formed in OPN mainly by intrinsically photosensitive RGCs, thereby partially restoring the pupillary light reflex (PLR).