Lipid Nanoparticle-Encapsulated TALEN-Encoding mRNA Inactivates Hepatitis B Virus Replication in Cultured Cells and Transgenic Mice
Tiffany Smith,
Prashika Singh,
Ridhwaanah Bhana,
Dylan Kairuz,
Kristie Bloom,
Mohube Betty Maepa,
Abdullah Ely,
Patrick Arbuthnot
Affiliations
Tiffany Smith
Wits/SAMRC Antiviral Gene Therapy Research Unit, Infectious Diseases and Oncology Research Institute (IDORI), School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa
Prashika Singh
Wits/SAMRC Antiviral Gene Therapy Research Unit, Infectious Diseases and Oncology Research Institute (IDORI), School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa
Ridhwaanah Bhana
Wits/SAMRC Antiviral Gene Therapy Research Unit, Infectious Diseases and Oncology Research Institute (IDORI), School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa
Dylan Kairuz
Wits/SAMRC Antiviral Gene Therapy Research Unit, Infectious Diseases and Oncology Research Institute (IDORI), School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa
Kristie Bloom
Wits/SAMRC Antiviral Gene Therapy Research Unit, Infectious Diseases and Oncology Research Institute (IDORI), School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa
Mohube Betty Maepa
Wits/SAMRC Antiviral Gene Therapy Research Unit, Infectious Diseases and Oncology Research Institute (IDORI), School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa
Abdullah Ely
Wits/SAMRC Antiviral Gene Therapy Research Unit, Infectious Diseases and Oncology Research Institute (IDORI), School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa
Patrick Arbuthnot
Wits/SAMRC Antiviral Gene Therapy Research Unit, Infectious Diseases and Oncology Research Institute (IDORI), School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa
Chronic infection with the hepatitis B virus (HBV) results in over 1 million deaths annually. Although currently licensed treatments, including pegylated interferon-α and nucleoside/nucleotide analogs, can inhibit viral replication, they rarely eradicate covalently closed circular DNA (cccDNA) reservoirs. Moreover, vaccination does not offer therapeutic benefit to already infected individuals or non-responders. Consequently, chronic infection is maintained by the persistence of cccDNA in infected hepatocytes. For this reason, novel therapeutic strategies that permanently inactivate cccDNA are a priority. Obligate heterodimeric transcription activator-like effector nucleases (TALENs) provide the precise gene-editing needed to disable cccDNA. To develop this strategy using a therapeutically relevant approach, TALEN-encoding mRNA targeting viral core and surface genes was synthesized using in vitro transcription with co-transcriptional capping. TALENs reduced hepatitis B surface antigen (HBsAg) by 80% in a liver-derived mammalian cell culture model of infection. In a stringent HBV transgenic murine model, a single dose of hepatotropic lipid nanoparticle-encapsulated TALEN mRNA lowered HBsAg by 63% and reduced viral particle equivalents by more than 99%, without evidence of toxicity. A surveyor assay demonstrated mean in vivo HBV DNA mutation rates of approximately 16% and 15% for Core and Surface TALENs, respectively. This study presents the first evidence of the therapeutic potential of TALEN-encoding mRNA to inactivate HBV replication permanently.
