Functions of transforming growth factor-β isoforms in the nervous system -: Cues based on localization and experimental in vitro and in vivo evidence

This review briefly describes the cellular distribution and documented roles of the transforming growth factor (TGF)-beta isoforms TGF-beta2 and -beta3 in the central and peripheral nervous system. TGF-beta2 and -beta3 are coexpressed in developing radial glial and mature astroglial and Schwann cells, as well as in subpopulations of differentiated neurons, most prominently in cortical, hippocampal, and brainstem/spinal cord motor neurons. In vitro studies have suggested a number of potential, physiologically relevant functions for TGF-betas including regulation of astroglial cell proliferation, expression of adhesion molecules, survival promoting roles for neurons in combination with established neurotrophic factors, and differentiative actions on neurons.