Transplanted embryonic neurons integrate into adult neocortical circuits

摘要: The ability of the adult mammalian brain to compensate for neuronal loss caused by injury or disease is very limited. Transplantation aims replace lost neurons, but extent which new neurons can integrate into existing circuits unknown. Here, using chronic in vivo two-photon imaging, we show that embryonic transplanted visual cortex mice mature bona fide pyramidal cells with selective pruning basal dendrites, achieving adult-like densities dendritic spines and axonal boutons within 4-8 weeks. Monosynaptic tracing experiments reveal grafted receive area-specific, afferent inputs matching those normal cortex, including topographically organized geniculo-cortical connections. Furthermore, stimulus-selective responses refine over course many weeks finally become indistinguishable from host neurons. Thus, great specificity neocortical normally never incorporate brain.