The urodele amphibians are nearly the only adult vertebrates able to regenerate 
their missing or amputated tail. The most striking feature of this model lies in 
the ability of the spinal cord (SC) to differentiate, within the regenerating 
tail, a new ependymal tube from which the SC and the peripheral nervous system 
originate. A fundamental question is whether, in response to tail excision, the 
ependymoglia of the old SC stump behaves as an embryonic neuroepithelium. To 
evaluate this possibility, cell lines from primary cell cultures of adult SC 
were established for the first time in newts, and two cell clones, 
immunochemically characterized as ependymoglial cell populations, could be 
obtained. To analyze the potentialities of these clonal cells, after 
transplantation in tail regenerates, cell-marking experiments, using either in 
vitro transfection with lacZ gene or the lineage tracer lysinated rhodamine 
dextran (LRD), were performed. One to 2 weeks postimplantation, most of labeled 
derivatives were identified as melanocytes. Interestingly, labeled cells were 
also seen integrated in the ependymoglia of the regenerating SC. Two to 6 weeks 
after implantation in young regenerates, we also observed LRD-labeled elongated 
cells close to nerves or myofibers which were unambiguously identified as 
Schwann cells by galactocerebroside staining. Taken together, these findings 
showed that clonal cells derived from adult newt SC cultures could largely find, 
in regenerate mesenchyme, suitable environmental conditions to differentiate 
into melanocytes or Schwann cells. Because these two cells types arise from 
neural crest cells during embryo-genesis, this supports the interesting view 
that multipotent cells are still present in the SC of adult urodeles.