Reversal of diabetes in a humanised mouse using a clinically applicable vector system

Project Member(s): Simpson, A.

Funding or Partner Organisation: National Health & Medical Research Council (National Health Medical Research Council)

Start year: 2015

Summary: Gene therapy is a possible cure for diabetes. We have established that following isolation of the liver from the circulation by a surgical technique (FFO), the lentiviral delivery human insulin (INS) directly into the liver of diabetic rats and NOD mice, resulted in normal glucose responsiveness and permanent reversal of diabetes. This was associated with partial endocrine pancreatic transdifferentiation (PT) of the liver and expression of ß cell transcription factors (ß cell TF). However, this approach using the lentiviral vector has its limitations for clinical translation due to the surgical procedure. In this proposal we aim to use a clinically applicable adeno-associated viral vector (AAV) rAAV-LK03 and the FRG mouse model (chimeric human/ mouse livers) to design a protocol for reversing diabetes in human hepatocytes (HH). As the FRG model is expensive to prepare NOD/scid mice will be used to establish the study parameters. The aims are to determine (1 & 2) If the delivery of INS by AAV into the livers of diabetic NOD/scid mice results in reversal of diabetes without the FFO procedure and if the presence of ß cell TF initiates PT and/ or increases the efficiency of the process; (3) If the delivery of INS ± a ß cell TF by rAAV-LK03 into the livers of diabetic FRG mice results in the expression of a ß-cell phenotype in HH with reversal of diabetes; (4) The kinetics of the PT and the phenotype of transduced HH. Diabetic NOD/scid and FRG (engrafted with HH) will be transduced with INS ± ß cell TF. Following reversal of diabetes an intravenous glucose tolerance test will be performed. Liver tissue will be subjected to immunohistochemistry and RT-PCR to detect mouse and human ß cell TFs. Human liver cells will be isolated and the phenotype of transduced cells will be determined by real-time PCR and differential expression profiles by microarrays at several timepoints. If successful this project will show reversal of diabetes in HH using a clinically applicable AAV.

Publications:

LA, QT, REN, B, LOGAN, GJ, CUNNINGHAM, SC, KHANDEKAR, N, NASSIF, NT, O'BRIEN, BA, ALEXANDER, IE & SIMPSON, AM 1970, '1778-P: Delivery of the Insulin Gene Using an Integrating Adeno-Associated Viral Vector (AAV) to Diabetic NOD Mice', Diabetes, 79th Scientific Sessions of the American-Diabetes-Association (ADA), American Diabetes Association, San Francisco, CA, pp. 1778-P.
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Gerace, D, Martiniello-Wilks, R, Nassif, NT, Lal, S, Steptoe, R & Simpson, AM 2017, 'CRISPR-targeted genome editing of mesenchymal stem cell-derived therapies for type 1 diabetes: a path to clinical success?', Stem Cell Research & Therapy, vol. 8, no. 1.
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Simpson, A, Ren, B, O'Brien, BA, Alexander, IE, Nassif, NT, Tan, Y & Martiniello-Wilks, R 2015, 'GENE THERAPY FOR DIABETES: REVERSAL OF DIABETES IN THE HUMANISED FRG MOUSE MODEL.', LIPPINCOTT WILLIAMS & WILKINS, pp. S67-S67.

FOR Codes: Clinical Sciences, Diabetes, Clinical health