Influence of transplant location on survival and proliferation of grafted human neural cell lines in adult rats

Two human neural cell lines were examined after intracerebral transplantati on in non-immunosuppressed adult rats. BE(2)-M17 neuroblastoma cells or NT2 teratocarcinoma cells genetically modified with the tyrosine hydroxylase ( TH) gene were transplanted into four brain regions: neocortex, cerebellum, striatum and amygdala. The survival and proliferation of both cell lines de pended on the transplant location. Grafted NT2 or M17 cells survived up to 8 weeks in the neocortex while in the cerebellum, striatum or amygdala did not. M17 cells generated tumors in 85% of the rats with striatum or amygdal a grafts. M17 cells grafted into the neocortex and cerebellum ceased prolif erating and survived for longer. No animals with NT2 grafts died of a tumor at any of the post-transplant times studied. M17 cells and some NT2 cells stained for TH in vitro, but the cells failed to stain for TH io vivo.