The neurotrophins act synergistically with LIF and members of the TGF-betasuperfamily to promote the survival of spiral ganglia neurons in vitro

A number of growth factor families have been implicated in normal inner ear development, auditory neuron survival and protection. Several growth facto rs, including transforming growth factor-beta 5 (TGF-beta 5) and TGF-beta 3 , neurotrophin-3 (NT-3), brain-derived neurotrophic factor (BDNF) and leuke mia inhibitory factor (LIF) were tested for their ability, individually or in combination, to promote auditory neuron survival in dissociated cell cul tures of early rat post-natal spiral ganglion cells (SGCs). The results ind icate that at discrete concentrations all growth factors act in an additive fashion and some in synergy when promoting neuronal survival. These findin gs support the hypothesis that growth factors from different families may b e interdependent when sustaining neuronal integrity. (C) 1999 Elsevier Scie nce B.V. All rights reserved.