Axonal growth from insect neurons in glia-free cultures.

Mechanical dissociation of nerve and glial cells from 16-day embryos of the cockroach Periplaneta americana and their subsequent culture in a Co(2)-conditioned, chemically defined medium results in the survival of neurons but not of glial cells. The dissociated nerve cells remain alive and in excellent condition for many months and build a dense fibrillar network in presence of foregut explants from the same embryos. These explants are invaded by numerous and large fiber bundles emerging from the fibrillar network. The morphological characteristics of nerve cells and the structural and ultrastructural features of nerve bundles in long-term glia-free culture are described.