Human hepatitis D virus-specific T cell epitopes

Matin Kohsar; Johanna Landahl; Christoph Neumann-Haefelin; Julian Schulze Zur Wiesch

doi:10.1016/j.jhepr.2021.100294

Human hepatitis D virus-specific T cell epitopes

JHEP Rep. 2021 Apr 23;3(4):100294. doi: 10.1016/j.jhepr.2021.100294. eCollection 2021 Aug.

Authors

Matin Kohsar¹, Johanna Landahl^{1

2}, Christoph Neumann-Haefelin³, Julian Schulze Zur Wiesch^{1

4}

Affiliations

¹ I. Medical Department (Gastroenterology with the Sections Infectiology and Tropical Medicine), University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
² AKK Altonaer Kinderkrankenhaus gGmbH, Bleickenallee 38, 22763 Hamburg, Germany.
³ Department of Medicine II (Gastroenterology, Hepatology, Endocrinology, and Infectious Diseases), Freiburg University Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
⁴ German Center for Infection Disease (DZIF), University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.

Abstract

HDV is a small, defective RNA virus that requires the HBsAg of HBV for its assembly, release, and transmission. Chronic HBV/HDV infection often has a severe clinical outcome and is difficult to treat. The important role of a robust virus-specific T cell response for natural viral control has been established for many other chronic viral infections, but the exact role of the T cell response in the control and progression of chronic HDV infection is far less clear. Several recent studies have characterised HDV-specific CD4+ and CD8+ T cell responses on a peptide level. This review comprehensively summarises all HDV-specific T cell epitopes described to date and describes our current knowledge of the role of T cells in HDV infection. While we now have better tools to study the adaptive anti-HDV-specific T cell response, further efforts are needed to define the HLA restriction of additional HDV-specific T cell epitopes, establish additional HDV-specific MHC tetramers, understand the degree of cross HDV genotype reactivity of individual epitopes and understand the correlation of the HBV- and HDV-specific T cell response, as well as the breadth and specificity of the intrahepatic HDV-specific T cell response.

Keywords: ADAR1, adenosine deaminases acting on RNA; ALT, alanine aminotransferase; AST, aspartate aminotransferase; CD4+; CD8+; ELISpot, enzyme-linked immune spot assay; HBV; HDAg, hepatitis delta antigen; HDV; Hepatitis Delta; ICS, intracellular cytokine staining; IFN-, interferon-; L-HDAg, large hepatitis delta antigen; MAIT, mucosa-associated invariant T cells; NK cells, natural killer cells; NTCP, sodium taurocholate co-transporting polypeptide; PBMCs, peripheral blood mononuclear cells; PD-1, programmed cell death protein 1; PTM, post-translational modification; Peg-IFN-α, pegylated interferon alpha; S-HDAg, small hepatitis delta antigen; T cell; TCF, T cell-specific transcription factor; TNFα, tumour necrosis factor-α; Th1, T helper 1; aa, amino acid(s); cccDNA, covalently closed circular DNA; epitope; viral escape.

Publication types

Review