title: CCL3/MIP-1alpha is pro-inflammatory in murine T cell-mediated hepatitis by recruiting CCR1-expressing CD4(+) T cells to the liver.
abstract: T cell-mediated hepatitis is associated with significant morbidity and mortality worldwide. Levels of C-C chemokine ligand 3/macrophage inflammatory protein-1alpha (CCL3/MIP-1alpha) are elevated in the serum of patients with T cell-mediated liver diseases, but its role is not fully understood. Con A-induced hepatitis is a murine liver-specific inflammation mediated by activated T cells and is driven by an up-regulation of the hepatic expression of IFN-gamma. In this study, we have used CCL3/MIP-1alpha gene-deficient mice to examine the role of CCL3/MIP-1alpha in the pathogenesis of Con A-induced hepatitis. We demonstrate a novel pro-inflammatory role for CCL3/MIP-1alpha since CCL3/MIP-1alpha deficiency significantly attenuated hepatic injury, both biochemically and histologically. Moreover, the recruitment of CCR1-expressing CD4(+) T cells to the liver after Con A treatment was strikingly attenuated by CCL3/MIP-1alpha deficiency. Correspondingly, hepatic IFN-gamma produced by the recruited CD4(+) T cells was significantly reduced by CCL3/MIP-1alpha deficiency during Con A-induced hepatitis. Furthermore, treatment of mice with a dual CCR1/CCR5 peptide antagonist, methionylated RANTES, also markedly reduced hepatic injury and decreased the numbers of CD4(+) T cells within the liver producing IFN-gamma during Con A-induced hepatitis. These findings demonstrate that blockade of the CCL3/MIP-1alpha-CCR1 pathway may represent a novel therapeutic target for treating T cell-mediated liver diseases.
authors.affiliation: Liver Unit, Gastrointestinal Research Group, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Maureen N
authors.initials: MN
authors.lastname: Ajuebor
authors.forename: Cory M
authors.initials: CM
authors.lastname: Hogaboam
authors.forename: Tai
authors.initials: T
authors.lastname: Le
authors.forename: Amanda E I
authors.initials: AE
authors.lastname: Proudfoot
authors.forename: Mark G
authors.initials: MG
authors.lastname: Swain
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D056486:Chemical and Drug Induced Liver Injury / Q000276:immunology* / Q000473:pathology; D054405:Chemokine CCL3; D054407:Chemokine CCL4; D018946:Chemokine CCL5 / Q000494:pharmacology; D003208:Concanavalin A / Q000494:pharmacology; D004195:Disease Models, Animal; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D007371:Interferon-gamma / Q000032:analysis / Q000187:drug effects / Q000276:immunology; D008099:Liver / Q000276:immunology* / Q000473:pathology; D019402:Macrophage Inflammatory Proteins / Q000172:deficiency / Q000276:immunology*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D020556:Neutrophil Infiltration / Q000187:drug effects / Q000276:immunology; D054389:Receptors, CCR1; D019713:Receptors, CCR5 / Q000276:immunology; D019707:Receptors, Chemokine / Q000276:immunology*
chemical_list: C515301:Ccr1 protein, mouse; D054405:Chemokine CCL3; D054407:Chemokine CCL4; D018946:Chemokine CCL5; D019402:Macrophage Inflammatory Proteins; D054389:Receptors, CCR1; D019713:Receptors, CCR5; D019707:Receptors, Chemokine; D003208:Concanavalin A; D007371:Interferon-gamma