Neuronal targeting of cardiotrophin-1 by coupling with tetanus toxin C fragment.
Cardiotrophin-1 (CT-1) is a potent neurotrophic factor for motoneurons but its clinical use in motor neuron diseases is precluded by side effects on the heart and liver. We explored the possibility of targeting CT-1 to neurons by coupling with the tetanus toxin fragment TTC. Genetic fusion proteins between CT-1 or GFP and TTC were produced in Escherichia coli and assayed in vitro. In contrast to uncoupled CT-1 or GFP, TTC-coupled proteins bound with high affinity to cerebral neurons and spinal cord motoneurons and were rapidly internalized. Glia, hepatocytes, or cardiomyocytes did not show detectable binding or uptake of TTC-coupled proteins. Similar to CT-1, TTC-coupled CT-1 induced IL-6 secretion by KB cells, activated Reg-2 gene expression, and promoted motoneuron survival in a dose-dependent manner. In vivo studies will test whether TTC-coupled CT-1 might be targeted to degenerating spinal cord or brain-stem motoneurons and migrate trans-synaptically to cortical motoneurons, which are also affected in amyotrophic lateral sclerosis.
Bordet
T
T
INSERM U.129, Institut Cochin de Génétique Moléculaire, 24, Rue du Faubourg St Jacques, 75014 Paris, France.
Castelnau-Ptakhine
L
L
Fauchereau
F
F
Friocourt
G
G
Kahn
A
A
Haase
G
G
D000818:Animals; D001921:Brain / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D016207:Cytokines / Q000235:genetics / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000235:genetics; D005333:Fetus; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D049452:Green Fluorescent Proteins; D006321:Heart / Q000187:drug effects / Q000502:physiology; D022781:Hepatocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D008164:Luminescent Proteins / Q000032:analysis / Q000235:genetics; D051379:Mice; D016472:Motor Neuron Disease / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D009046:Motor Neurons / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D009414:Nerve Growth Factors / Q000235:genetics / Q000494:pharmacology*; D010446:Peptide Fragments / Q000235:genetics / Q000494:pharmacology*; D015202:Protein Engineering / Q000379:methods; D011993:Recombinant Fusion Proteins / Q000138:chemical synthesis / Q000235:genetics / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics; D013116:Spinal Cord / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D013744:Tetanus Toxin / Q000235:genetics / Q000494:pharmacology*
D016207:Cytokines; D015850:Interleukin-6; D008164:Luminescent Proteins; D009414:Nerve Growth Factors; D010446:Peptide Fragments; D011993:Recombinant Fusion Proteins; D013744:Tetanus Toxin; C040635:tetanus toxin fragment C; D049452:Green Fluorescent Proteins; C092073:cardiotrophin 1