title: Activation of Flucloxacillin-Specific CD8+ T-Cells With the Potential to Promote Hepatocyte Cytotoxicity in a Mouse Model.
abstract: There are currently no animal models of drug-induced liver injury (DILI) where the adaptive immune system has been shown to damage the liver. Thus, it is difficult to explore the mechanistic basis of the tissue injury. The aim of this study was to use C57BL/6 CD4+-deficient mice with a mutation in the αβ gene encoding for Major histocompatibilty complex (MHC) class II molecules to (1) develop a mouse model of flucloxacillin sensitization, (2) explore whether drug-specific CD8+ kill primary hepatocytes, and (3) analyze perturbations in liver integrity following oral exposure to flucloxacillin. CD8+ T-cells from lymph nodes of flucloxacillin-sensitized mice were stimulated to proliferate, secrete interferon (IFN-γ) and granzyme B, and induce hepatocyte apoptosis in a concentration-dependent manner following ex vivo stimulation. The T-cell response was antigen-specific; T-cells were not activated with other β-lactam antibiotics. Furthermore, T-cell responses only occurred in the presence of flucloxacillin-pulsed antigen presenting cells. In separate experiments, flucloxacillin-specific T-cells were induced to migrate to the mesenteric lymph nodes using retinoic acid, prior to administration of oral flucloxacillin, and analysis of plasma biomarkers of liver injury. Oral exposure to flucloxacillin resulted in mild elevations in alanine aminotransferase, liver, and gall bladder leukocyte infiltration and a marked swelling of the gall bladder. Thus, CD4+-deficient mice represent a promising model to study the role of the adaptive immune system in DILI.
authors: *Department of Pharmacology, MRC Centre for Drug Safety Science, The University of Liverpool, Liverpool L69 3GE, UK.
authors: Ryan
authors: R
authors: Nattrass
authors: *Department of Pharmacology, MRC Centre for Drug Safety Science, The University of Liverpool, Liverpool L69 3GE, UK.
authors: Lee
authors: L
authors: Faulkner
authors: International Center for Infectiology Research, Inserm, U1111, University of Lyon 1 69007, Lyon, France.
authors: Marc
authors: M
authors: Vocanson
authors: *Department of Pharmacology, MRC Centre for Drug Safety Science, The University of Liverpool, Liverpool L69 3GE, UK.
authors: Daniel J
authors: DJ
authors: Antoine
authors: *Department of Pharmacology, MRC Centre for Drug Safety Science, The University of Liverpool, Liverpool L69 3GE, UK, AstraZeneca R&D, Alderley Park, Macclesfield SK10 4TF, UK and.
authors: Anja
authors: A
authors: Kipar
authors: Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, 268 8057 Zurich, Switzerland.
authors: Gerry
authors: G
authors: Kenna
authors: International Center for Infectiology Research, Inserm, U1111, University of Lyon 1 69007, Lyon, France.
authors: Jean-Francois
authors: JF
authors: Nicolas
authors: *Department of Pharmacology, MRC Centre for Drug Safety Science, The University of Liverpool, Liverpool L69 3GE, UK.
authors: B Kevin
authors: BK
authors: Park
authors: *Department of Pharmacology, MRC Centre for Drug Safety Science, The University of Liverpool, Liverpool L69 3GE, UK, dnes@liv.ac.uk.
authors: Dean J
authors: DJ
authors: Naisbitt
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects*; D005436:Floxacillin / Q000494:pharmacology*; D022781:Hepatocytes / Q000187:drug effects*; D051379:Mice
chemical_list: D000900:Anti-Bacterial Agents; D005436:Floxacillin
keywords: flucloxacillin; immunogenicity; liver injury