444. Use of dsAAV8-Mediated Gene Transfer to Endogenous β-Cells To Investigate the Therapeutic Efficacy of Immunoregulatory Gene Products in Preventing the Onset of Diabetes in NOD Mice
Authors: Khaja K. Rehman, Zhong Wang, Xiao Xiao, Paul D. Robbins
Journal: Molecular Therapy (2006)

The non-obese diabetic (NOD) mouse represents an animal model of human type 1 diabetes, developing spontaneous autoimmune diabetes. Previously, we have shown that intra-peritoneal (i.p.), intravenous (i.v.) or intra-ductal (i.d.) delivery of certain AAV serotypes stably transduces the pancreas and, in particular, the islets1. The endogenous β-cells within the islets were best transduced by AAV8 via the i.p. and i.v. routes, but by AAV6 via the pancreatic i.d. route. We also have been able to deliver and express genes specifically in β-cells for at least 6 months using an insulin promoter in a double-stranded, self-complementary AAV vector (dsAAV-Ins). This ability to deliver and express gene products specifically in β- cells using a dsAAV8-Ins vector allows for the testing of specific gene products in regulating progression of β-cell destruction and the onset of hyperglycemia in NOD mice. We have evaluated the effects of dsAAV8-Ins delivery of interleukin-4 (IL-4) and interleukin-10 (IL-10) to β-cells in NOD mice, using a dsAAV8-Ins-eGFP vector as a control. In female NOD mice, the extent of gene transfer to endogenous β-cells following i.p. delivery of dsAAV8-Ins-eGFP was comparable to normal Balb/C mice. Furthermore, following i.p. delivery of dsAAV8-Ins-IL-4 or IL-10, expression of IL-4 and IL-l0 cytokine was detected in islets isolated and cultured at different time points post-injection. Expression of IL-4 in β-cells prevented the onset of hyperglycemia in NOD mice whereas expression of IL-10 enhanced the time of onset of hyperglycemia. These results demonstrate the utility of using the dsAAV8-Ins vector to transfer immuno-regulatory agents to endogenous β-cells in NOD mice to examine their role in preventing or exacerbating capable the onset of type 1 diabetes. The non-obese diabetic (NOD) mouse represents an animal model of human type 1 diabetes, developing spontaneous autoimmune diabetes. Previously, we have shown that intra-peritoneal (i.p.), intravenous (i.v.) or intra-ductal (i.d.) delivery of certain AAV serotypes stably transduces the pancreas and, in particular, the islets1. The endogenous β-cells within the islets were best transduced by AAV8 via the i.p. and i.v. routes, but by AAV6 via the pancreatic i.d. route. We also have been able to deliver and express genes specifically in β-cells for at least 6 months using an insulin promoter in a double-stranded, self-complementary AAV vector (dsAAV-Ins). This ability to deliver and express gene products specifically in β- cells using a dsAAV8-Ins vector allows for the testing of specific gene products in regulating progression of β-cell destruction and the onset of hyperglycemia in NOD mice. We have evaluated the effects of dsAAV8-Ins delivery of interleukin-4 (IL-4) and interleukin-10 (IL-10) to β-cells in NOD mice, using a dsAAV8-Ins-eGFP vector as a control. In female NOD mice, the extent of gene transfer to endogenous β-cells following i.p. delivery of dsAAV8-Ins-eGFP was comparable to normal Balb/C mice. Furthermore, following i.p. delivery of dsAAV8-Ins-IL-4 or IL-10, expression of IL-4 and IL-l0 cytokine was detected in islets isolated and cultured at different time points post-injection. Expression of IL-4 in β-cells prevented the onset of hyperglycemia in NOD mice whereas expression of IL-10 enhanced the time of onset of hyperglycemia. These results demonstrate the utility of using the dsAAV8-Ins vector to transfer immuno-regulatory agents to endogenous β-cells in NOD mice to examine their role in preventing or exacerbating capable the onset of type 1 diabetes.