The recent molecular cloning of
BDNF and
CNTF based on traditional
protein purification and
protein sequencing and the identification and cloning of NT-3 and
NT-4 by homology cloning strategies has led to a tremendous flurry of interest in the biology of these
proteins and initiation of studies to assess their potential utility in
neurological disorders ranging through degenerative disease,
stroke and
ischemia,
trauma and
peripheral neuropathies. Tissue culture studies have been very useful in identifying neuronal specificities of the
neurotrophins and
CNTF and in combination with localization studies of these
growth factors and their receptors have provided the basis for in vivo studies. Initial animal studies with
BDNF indicate efficacy of
BDNF in models of Alzheimer's and
Parkinson's disease and small fiber sensory neuropathy. Studies with
CNTF have similarly progressed from in vitro findings, especially the discovery that
CNTF is a
growth factor for motor neurons, to in vivo findings where
CNTF has been shown to be effective in slowing symptoms of motor neuron dysfunction in three genetic models. Based on these positive animal data,
CNTF is currently in clinical trials for the potential treatment of
motor neuron disease or
amyotrophic lateral sclerosis (ALS), also known as
Lou Gehrig's disease.