Safety and in vivo Expression of a GNE-Transgene: A Novel Treatment Approach for Hereditary Inclusion Body Myopathy-2

• Published in: Gene regulation and systems biology 2009-01, Vol.2009 (3), p.89-101
• Main Authors: Phadke, Anagha P., Jay, Chris, Chen, Salina J., Haddock, Courtney, Wang, Zhaohui, Yu, Yang, Nemunaitis, Derek, Nemunaitis, Gregory, Templeton, Nancy S., Senzer, Neil, Maples, Phillip B., Tong, Alex W., Nemunaitis, John
• Format: Article
• Language: English
• Subjects: Cytomegalovirus; Encapsulation; Expression vectors; Gene expression; Gene regulation; Gene therapy; Inclusion bodies; Intravenous administration; Liposomes; Muscles; Muscular diseases; Mutation; Original Research; Plasmids; Side effects; Toxicity; Transgenes
• ISSN: 1177-6250; 1177-6250
• DOI: 10.4137/GRSB.S2210

Anagha P. Phadke1, Chris Jay1, Salina J. Chen1, Courtney Haddock1, Zhaohui Wang1, Yang Yu1, Derek Nemunaitis1, Gregory Nemunaitis2,4, Nancy S. Templeton3, Neil Senzer1,4,5,6, Phillip B. Maples1, Alex W. Tong1 and John Nemunaitis1,4,5,61Gradalis, Inc., Dallas, TX. 2MetroHealth Medical Center, Cleveland, OH. 3Baylor College of Medicine, Houston, TX. 4Mary Crowley Cancer Research Centers. 5Texas Oncology PA. 6Baylor Sammons Cancer Center, Dallas, TX.AbstractHereditary inclusion body myopathy-2 (HIBM2) is an adult-onset, muscular disease caused by mutations in the GNE gene. HIBM2-associated GNE mutations causing hyposialyation have been proposed to contribute to reduced muscle function in patients with HIBM2, though the exact cause of this disease is unknown. In the current studies we examined pre-clinical in vivo toxicity, and expression of the plasmid-based, CMV driven wild-type GNE plasmid vector. The plasmid vector was injected intramuscularly (IM) or systemically (IV) into BALB/c mice, following encapsulation in a cationic liposome (DOTAP:Cholesterol). Single IM injections of the GNE-lipoplex at 40 μg did not produce overt toxicity or deaths, indicating that the no observable adverse effect level (NOAEL) dose for IM injection was ≥40 μg. Single intravenous (IV) infusion of GNE-lipoplex was lethal in 33% of animals at 100 μg dose, with a small proportion of animals in the 40 μg cohort demonstrating transient toxicity. Thus the NOAEL dose by the IV route was greater than 10 μg and less than or equal to 40 μg. Real-time RT-qPCR analysis demonstrated recombinant human GNE mRNA expression in 100% of muscle tissues that received IM injection of 40 μg GNE-lipoplex, at 2 weeks. These results indicate that GNE-lipoplex gene transfer is safe and can produce durable transgene expression in treated muscles. Our findings support future exploration of the clinical efficacy of GNE-lipoplex for experimental gene therapy of HIBM2.