MHC-E–Restricted CD8+ T Cells Target Hepatitis B Virus–Infected Human Hepatocytes
Benjamin J. Burwitz, Patrick K Hashiguchi, Mandana Mansouri, Christine Meyer, Roxanne M. Gilbride, Sreya Biswas, Jennie Womack, Jason S. Reed, Helen L. Wu, Michael K. Axthelm, Scott G. Hansen, Louis J. Picker, Klaus Früh, Jonah B. Sacha
Abstract
Abstract Currently 247 million people are living with chronic hepatitis B virus infection (CHB), and the development of novel curative treatments is urgently needed. Immunotherapy is an attractive approach to treat CHB, yet therapeutic approaches to augment the endogenous hepatitis B virus (HBV)–specific T cell response in CHB patients have demonstrated little success. In this study, we show that strain 68-1 rhesus macaque (RM) CMV vaccine vectors expressing HBV Ags engender HBV-specific CD8+ T cells unconventionally restricted by MHC class II and the nonclassical MHC-E molecule in RM. Surface staining of human donor and RM primary hepatocytes (PH) ex vivo revealed the majority of PH expressed MHC-E but not MHC class II. HBV-specific, MHC-E–restricted CD8+ T cells from RM vaccinated with RM CMV vaccine vectors expressing HBV Ags recognized HBV-infected PH from both human donor and RM. These results provide proof-of-concept that MHC-E–restricted CD8+ T cells could be harnessed for the treatment of CHB, either through therapeutic vaccination or adoptive immunotherapy.