Xenografts of embryonic nerve tissue from Drosophila neuromutants stimulate development of neural homografts in rat brain and block glial scar formation.

The influence of xenografts of Drosophila melanogaster embryonic nerve cells on the development of embryonic neurohomografts in the adult rat brain has been investigated. Embryonic nerve cells, marked with bacterial galactosidase gene (lacZ) from D. melanogaster strain with a mutation in the Delta locus, were transplanted into adult rat brain. Drosophila cells were easily identifiable in brain histological sections by X-gal staining. Xenografts survived for at least 2-3 weeks in the recipient brain after the operation to be subsequently attacked by macrophages. Importantly, no glial scar was formed around the xenograft. The addition of Drosophila embryonic nerve cells to a homograft of rat embryonic neural tissue facilitated the survival and development of this homograft by blocking the glial scar formation, stimulating vascularization of the graft area and differentiation of the implanted embryonic nerve cells.