title: Ciliary neurotrophic factor fused to a protein transduction domain retains full neuroprotective activity in the absence of cytokine-like side effects.
abstract: Ciliary neurotrophic factor (CNTF) is a multifunctional cytokine that can regulate the survival and differentiation of many types of developing and adult neurons. CNTF prevents the degeneration of motor neurons after axotomy and in mouse mutant progressive motor neuronopathy, which has encouraged trials of CNTF for human motor neuron disease. Given systemically, however, CNTF causes severe side effects, including cachexia and a marked immune response, which has limited its clinical application. The present work describes a novel approach for administering recombinant human CNTF (rhCNTF) while conserving neurotrophic activity and avoiding deleterious side effects. rhCNTF was fused to a protein transduction domain derived from the human immunodeficiency virus-1 TAT (transactivator) protein. The resulting fusion protein (TAT-CNTF) crosses the plasma membrane within minutes and displays a nuclear localization. TAT-CNTF was equipotent to rhCNTF in supporting the survival of cultured chicken embryo dorsal root ganglion neurons. Local or subcutaneous administration of TAT-CNTF, like rhCNTF rescued motor neurons from death in neonatal rats subjected to sciatic nerve transection. In contrast to subcutaneous rhCNTF, which caused a 20-30% decrease in body weight in neonatal rats between postnatal days 2 and 7 together with a considerable fat mobilization in brown adipose tissue, TAT-CNTF lacked such side effects. Together, these results indicate that rhCNTF fused with the protein transduction domain/TAT retains neurotrophic activity in the absence of CNTFs cytokine-like side effects and may be a promising candidate for the treatment of motor neuron and other neurodegenerative diseases.
authors.affiliation: Department of Physiology and Biophysics, State University of Campinas, Campinas, Brazil.
authors.forename: Alexandre C
authors.initials: AC
authors.lastname: Rezende
authors.forename: Daniele
authors.initials: D
authors.lastname: Peroni
authors.forename: Andrè S
authors.initials: AS
authors.lastname: Vieira
authors.forename: Fabio
authors.initials: F
authors.lastname: Rogerio
authors.forename: Rafael L
authors.initials: RL
authors.lastname: Talaisys
authors.forename: Fabio T M
authors.initials: FT
authors.lastname: Costa
authors.forename: Francesco
authors.initials: F
authors.lastname: Langone
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Skaper
authors.forename: Alessandro
authors.initials: A
authors.lastname: Negro
mesh_terms: D002001:Adipose Tissue, Brown / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D019771:Axotomy / Q000379:methods; D001835:Body Weight / Q000187:drug effects; D002452:Cell Count / Q000379:methods; D002478:Cells, Cultured; D002642:Chick Embryo; D020934:Ciliary Neurotrophic Factor / Q000378:metabolism / Q000627:therapeutic use*; D006224:Cricetinae; D003412:Cricetulus; D004305:Dose-Response Relationship, Drug; D005727:Ganglia, Spinal / Q000166:cytology; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D009046:Motor Neurons / Q000187:drug effects / Q000502:physiology; D018696:Neuroprotective Agents / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D011993:Recombinant Fusion Proteins / Q000378:metabolism / Q000627:therapeutic use; D050796:STAT3 Transcription Factor / Q000378:metabolism; D020426:Sciatic Neuropathy / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D011984:Sensory Receptor Cells / Q000187:drug effects / Q000502:physiology; D014161:Transduction, Genetic / Q000379:methods; D054322:tat Gene Products, Human Immunodeficiency Virus / Q000235:genetics / Q000627:therapeutic use
chemical_list: D020934:Ciliary Neurotrophic Factor; D018696:Neuroprotective Agents; D011993:Recombinant Fusion Proteins; D050796:STAT3 Transcription Factor; D054322:tat Gene Products, Human Immunodeficiency Virus; D049452:Green Fluorescent Proteins