Maturation and integration of purified foetal neurons transplanted into the adult brain.

Fetal neural transplants presently developed as a therapeutic strategy for neurodegenerative diseases include both the neurons of interest and their cellular environment. These glial and vascular cells may be detrimental by, for instance, expressing foreign MHC antigens. This study was undertaken to determine whether purified neurons would survive transplantation into an adult host brain. Embryonic rat spinal neurons were purified by panning and transplanted into adult hosts' brain. During the first three weeks post-transplantation the grafts contained essentially packed immature neurons. Later transplants contained large, multipolar neurons, demonstrating the ability of transplanted neurons to mature in the adult environment. The adult host appears actively involved in the integration of such a transplant by complementing it with microglial and vascular cells.