title: Chimeric antigen receptor (CAR)-engineered T cells redirected against hepatitis C virus (HCV) E2 glycoprotein.
abstract: OBJECTIVE
  The recent availability of novel antiviral drugs has raised new hope for a more effective treatment of hepatitis C virus (HCV) infection and its severe sequelae. However, in the case of non-responding or relapsing patients, alternative strategies are needed. To this end we have used chimeric antigen receptors (CARs), a very promising approach recently used in several clinical trials to redirect primary human T cells against different tumours. In particular, we designed the first CARs against HCV targeting the HCV/E2 glycoprotein (HCV/E2).
  
  
  METHODS
  Anti-HCV/E2 CARs were composed of single-chain variable fragments (scFvs) obtained from a broadly cross-reactive and cross-neutralising human monoclonal antibody (mAb), e137, fused to the intracellular signalling motif of the costimulatory CD28 molecule and the CD3ζ domain. Activity of CAR-grafted T cells was evaluated in vitro against HCV/E2-transfected cells as well as hepatocytes infected with cell culture-derived HCV (HCVcc).
  
  
  RESULTS
  In this proof-of-concept study, retrovirus-transduced human T cells expressing anti-HCV/E2 CARs were endowed with specific antigen recognition accompanied by degranulation and secretion of proinflammatory and antiviral cytokines, such as interferon γ, interleukin 2 and tumour necrosis factor α. Moreover, CAR-grafted T cells were capable of lysing target cells of both hepatic and non-hepatic origin expressing on their surface the HCV/E2 glycoproteins of the most clinically relevant genotypes, including 1a, 1b, 2a, 3a, 4 and 5. Finally, and more importantly, they were capable of lysing HCVcc-infected hepatocytes.
  
  
  CONCLUSIONS
  Clearance of HCV-infected cells is a major therapeutic goal in chronic HCV infection, and adoptive transfer of anti-HCV/E2 CARs-grafted T cells represents a promising new therapeutic tool.
authors: Laboratorio di Microbiologia e Virologia, Università Vita-Salute San Raffaele, Milan, Italy.
authors: Giuseppe A
authors: GA
authors: Sautto
authors: Institute of Virology, Technische Universität München/Helmholtz Zentrum München, Munich, Germany.
authors: Karin
authors: K
authors: Wisskirchen
authors: Laboratorio di Microbiologia e Virologia, Università Vita-Salute San Raffaele, Milan, Italy.
authors: Nicola
authors: N
authors: Clementi
authors: Laboratorio di Microbiologia e Virologia, Università Vita-Salute San Raffaele, Milan, Italy.
authors: Matteo
authors: M
authors: Castelli
authors: Laboratorio di Microbiologia e Virologia, Università Vita-Salute San Raffaele, Milan, Italy.
authors: Roberta A
authors: RA
authors: Diotti
authors: Institute of Virology, Technische Universität München/Helmholtz Zentrum München, Munich, Germany.
authors: Julia
authors: J
authors: Graf
authors: Laboratorio di Microbiologia e Virologia, Università Vita-Salute San Raffaele, Milan, Italy.
authors: Massimo
authors: M
authors: Clementi
authors: Laboratorio di Microbiologia e Virologia, Università Vita-Salute San Raffaele, Milan, Italy.
authors: Roberto
authors: R
authors: Burioni
authors: Institute of Virology, Technische Universität München/Helmholtz Zentrum München, Munich, Germany.
authors: Ulrike
authors: U
authors: Protzer
authors: Laboratorio di Microbiologia e Virologia, Università Vita-Salute San Raffaele, Milan, Italy.
authors: Nicasio
authors: N
authors: Mancini
mesh_terms: D061067:Antibodies, Monoclonal, Humanized / Q000276:immunology / Q000627:therapeutic use; D060846:Cell Engineering / Q000379:methods*; D002478:Cells, Cultured; D016174:Hepacivirus / Q000276:immunology*; D006526:Hepatitis C / Q000276:immunology / Q000628:therapy* / Q000821:virology; D022781:Hepatocytes / Q000276:immunology / Q000821:virology; D006801:Humans; D007167:Immunotherapy / Q000379:methods*; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014759:Viral Envelope Proteins / Q000276:immunology*
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D011948:Receptors, Antigen, T-Cell; D014759:Viral Envelope Proteins; C091015:glycoprotein E2, Hepatitis C virus
keywords: HEPATITIS C; IMMUNE RESPONSE; IMMUNOLOGY IN HEPATOLOGY; IMMUNOTHERAPY; INFECTIOUS DISEASE