A TAT-modified fusion protein efficiently penetrates mouse hypoglossal nuclei from transduced ependyma.
Future gene therapy for brainstem variant amyotrophic lateral sclerosis may be technically difficult if gene therapy vectors are injected near vital cardiorespiratory centers or if large portions of the tongue and pharyngeal muscles must be peripherally injected for retrograde transport of vectors to motor neurons. In this study we show that it is possible to deliver recombinant proteins to the hypoglossal nuclei without brainstem or muscle injections, by taking advantage of enhanced uptake of fusion proteins containing the protein transduction domain from the human immunodeficiency virus TAT protein. Adenoviral vectors expressing either TAT-modified or native beta-glucuronidase (beta-gluc) were injected into the lateral cerebral ventricles of mice, transducing ventricular epithelium down to the level of the obex in the brainstem. There was significant uptake into the hypoglossal nuclei of TAT-modified but not native beta-glucuronidase. The TAT-modified beta-gluc appeared to encompass half or more of the hypoglossal nuclei as visualized by retrograde labeling with cholera toxin subunit b in adjacent sections. TAT-modification of gene products may allow a relatively non-invasive approach to brainstem gene therapy via cerebroventricular injection.
Alisky
Joseph Martin
JM
Program in Gene Therapy, Department of Internal Medicine, University of Iowa College of Medicine, Iowa City, IA 52242, USA. alisky.joseph@marshfieldclinic.org
Xia
Haibin
H
Davidson
Beverly L
BL
D000256:Adenoviridae / Q000235:genetics; D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D000818:Animals; D031608:Area Postrema / Q000166:cytology / Q000378:metabolism / Q000821:virology; D004805:Ependyma / Q000166:cytology / Q000378:metabolism / Q000821:virology; D020546:Fourth Ventricle / Q000166:cytology / Q000378:metabolism / Q000821:virology; D015696:Gene Products, tat / Q000235:genetics / Q000378:metabolism* / Q000627:therapeutic use; D015316:Genetic Therapy / Q000379:methods; D005822:Genetic Vectors / Q000235:genetics* / Q000627:therapeutic use; D005966:Glucuronidase / Q000235:genetics; D007002:Hypoglossal Nerve / Q000166:cytology / Q000378:metabolism* / Q000821:virology; D007276:Injections, Intraventricular; D008526:Medulla Oblongata / Q000166:cytology / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009046:Motor Neurons / Q000166:cytology / Q000378:metabolism; D017434:Protein Structure, Tertiary / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism* / Q000627:therapeutic use; D014161:Transduction, Genetic / Q000379:methods* / Q000639:trends; D014162:Transfection / Q000379:methods* / Q000639:trends
D015696:Gene Products, tat; D011993:Recombinant Fusion Proteins; D005966:Glucuronidase