Transcriptomic Analysis of Insulin-Secreting Murine Hepatocytes Transduced with an Integrating Adeno-Associated Viral Vector

Abstract

Type 1 Diabetes (T1D) is a chronic metabolic disorder for which current treatments are unable to prevent the onset of complications. Previously, we used an adeno-associated viral vector (AAV8) to deliver furin-cleavable human insulin (INS-FUR) to the livers of diabetic non-obese diabetic (NOD) mice to reverse T1D. The use of the traditional AAV8-INS-FUR vector could not bring about normoglycemia. However, this vector, coupled with a transposon system in the AAV8/piggyBac-INS-FUR vector, was able to do so. This study aimed to investigate the transcriptomic profiles of the livers of diabetic, AAV8-INS-FUR-transduced, and AAV8/piggyBac-INS-FUR-transduced NOD mice and compare these to the normal liver to identify genetic differences resulting from delivery of the AAV8/piggyBac-INS-FUR vector which produced normoglycemia. Differential gene expression was determined by RNA-Seq analysis and differentially expressed genes from each treatment were mapped onto cellular pathways to determine the treatments’ cell signaling and downstream effects. We observed distinct differences between the piggyBac-transduced and diabetic models, particularly in terms of metabolic function and the upregulation of key pancreatic markers in the liver of piggyBac-transduced animals. The success of the AAV8/piggyBac-INS-FUR vector in achieving normoglycemia through stable transduction was evident. However, further engineering is necessary to achieve complete pancreatic transdifferentiation of liver cells.

Keywords

• type 1 diabetes
• adeno-associated viral (AAV) vector
• piggyBac transposon vector
• RNA-Seq
• differential gene expression
• pancreatic transdifferentiation