Antagonism of CCL5 chemokine receptors during regression of liver fibrosis is associated with an intrahepatic shift towards pro-inflammatory macrophages

Aims: Chemokines mediate the progression but also the regression of liver fibrosis. We could recently show that antagonism of the chemokine CCL5 with Met-CCL5 accelerates the regression of liver fibrosis (Berres et al. JCI 2010). Here we aimed to investigate the underlying mechanisms for the faster resolution of liver scarring in this model. Methods: C57BL/6 mice were treated with CCl4 for eight weeks to induce severe fibrosis. At peak of fibrosis (3 days after the last CCl4 injection), mice received either Met-CCL5 (10µg/day) or vehicle for the next 7 days. Mice were sacrificed 6 and 10 days after the last CCl4…