This is a research planning grant to study the interaction of human central nervous system neurons with rat glia in defined medium in culture. The effects of cellular interaction in these co-cultures will be studied by monitoring glial proliferation and differentiation when neurons are added to mixed glial cultures. This will be assayed by immunocytochemistry with cell-specific monoclonal antibodies. Transmission electron microscopy will be used to document the extent of the glial-neuronal interaction in the co-cultures and to document the presence of myelin. Antibodies against a neuronal protein which acts as a glial mitogen will be added to the co-cultures to document perturbations in the glial- neuronal interactions. This work is important because little is known about the development of myelin in the human brain. Myelin is a fatty covering around axon; without myelin, animals have difficulty in moving, in sensory perception, and ultimately in living. It has been hard to study the development of human brains because until now there has not been available sufficient numbers of mature human neurons for investigation. These co-cultures use human neurons derived from a brain tumor along with other brain cells, called glia, from immature rats. In this way, we can study how human neurons interact with glia to set up normal brain cellular interactions by examining at a molecular level the process of myelination.
