**Author details**

**Figure 4.** rAAV2/8-ACE2 uptake by hepatocytes and a cascade of events triggered by ACE2 protein in activated hepatic stellate cells (HSCs) during fibrosis. rAAV-ACE2 particles use AAV receptor (AAV-R) on hepatocyte membrane to enter the cytoplasm, followed by translocation into nucleus where uncoating and releasing of single-stranded viral genome occurs. The complementary strand will then be synthesized to transcribe ACE2. Membrane bound ACE2 protein has an exclusive role of cleaving potent profibrotic peptide angiotensin II (Ang II) to antifibrotic peptide angiotensin-1-7 (Ang-(1–7)). While a reduction in local Ang II levels leads to a significant reduction in the activation of its receptor, Ang II type 1 (AT1-R), Ang-(1–7) working through its receptor, Mas (Mas-R), inhibits the AT1-R activated downstream signaling such as PKC- and NADPH-mediated ROS production in activated HSCs. This in turn inhibits the phosphorylation of MAPKs such as ERK1/2, JNK, and p38, leading to a reduction in proinflammatory cytokines such as IL-1, IL-6, IL-8, IFNγ, MCP-1, and TNFα and profibrotic cytokine TGFβ1. A reduction in the activity of TGFβ1 leads to a reduction in phosphorylation of its transcription factors, Smad2/3, resulting in the inhibition of secretion of matrix proteins such as collagens and fibronectins. Thus, rAAV-ACE2 helps improving hepatic fibrosis and thus, intrahepatic vascular tone, leading to an improvement in portal hypertension. PKC, protein kinase C; NADPH oxidase, nicotinamide adenine dinucleotide phosphate oxidase; IL, interleukin; IFNγ, interferon γ; MCP-1, monocyte chemotactic protein 1; TNFα, tumor necrosis factor α; TGFβ1, transforming growth factor-β1; ERK1/2, extracellular

regulated kinase1/2; JNK, C-Jun N-terminal kinase.

156 In Vivo and Ex Vivo Gene Therapy for Inherited and Non-Inherited Disorders

Indu Rajapaksha, Peter Angus and Chandana Herath\*

\*Address all correspondence to: cherath@unimelb.edu.au

The University of Melbourne, Melbourne, Australia
