Thirty-five years ago, when Stephen Kuffler and his colleagues at Harvard initiated a new era of research on the properties and functions of neuroglial cells, very few neuro scientists were impressed at the time with the hypothesis that neuroglial cells could have another, though more subtle, role to play in the nervous system than to provide static support to neurons. Today, very few neuroscientists are unaware of the fact that multiple interactions between neurons and glial cells have been described, and that they consti tute the basis for understanding the function and the pathology of the nervous system. Glial cells outnumber neurons and make up about one-half of the bulk of the nervous system. They are divided into two major classes: first, the macroglia, which include astrocytes and oligodendrocytes in the central nervous system, and the Schwann cells in the peripheral nervous system; and second, the microglial cells. These different classes of glial cells have different functions and contribute in different ways in the devel opment, function, and the pathology of the nervous system."

This book, which takes as its focus the biology and pathology of glial cells, pays special attention to the issues concerning the cellular and molecular interactions occurring between glia and neurons. Research over the last 30 years has shown that, contrary to previously held conceptions of the role of glial cells as being of secondary importance to that of neurons, they are major constituents of the nervous system, playing a pivotal role during development and adulthood. Moreover, recent evidence suggests that glial cells are involved in a number of disease states, some of which are still incurable, such as Alzheimer's disease, multiple sclerosis and other central and peripheral neuropathies. It is also well known that Schwann cells, the major glial cells of the peripheral nervous system, are unique in their ability to sustain and promote regeneration not only of peripheral but also of central neurons after traumatic injury. Thus the relatively new idea of repairing CNS damage through the transplantation of glial cells is an approach with great clinical potential. Bringing together contributions from expert researchers in the field, this is an informative and forward thinking approach to a continuously expanding field.