Macrophage Depletion Attenuates Extracellular Matrix Deposition and Ductular Reaction in a Mouse Model of Chronic Cholangiopathies

PLoS One. 2016 Sep 12;11(9):e0162286. doi: 10.1371/journal.pone.0162286. eCollection 2016.

Abstract

Chronic cholangiopathies, such as primary and secondary sclerosing cholangitis, are progressive disease entities, associated with periportal accumulation of inflammatory cells, encompassing monocytes and macrophages, peribiliary extracellular matrix (ECM) deposition and ductular reaction (DR). This study aimed to elucidate the relevance of macrophages in the progression of chronic cholangiopathies through macrophage depletion in a 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) mouse model. One group of mice received a single i.p. injection of Clodronate encapsulated liposomes (CLOLipo) at day 7 of a 14 day DDC treatment, while control animals were co-treated with PBSLipo instead. Mice were sacrificed after 7 or respectively 14 days of treatment for immunohistochemical assessment of macrophage recruitment (F4/80), ECM deposition (Sirius Red, Laminin) and DR (CK19). Macrophage depletion during a 14 day DDC treatment resulted in a significant inhibition of ECM deposition. Porto-lobular migration patterns of laminin-rich ECM and ductular structures were significantly attenuated and a progression of DR was effectively inhibited by macrophage depletion. CLOLipo co-treatment resulted in a confined DR to portal regions without amorphous cell clusters. This study suggests that therapeutic options selectively directed towards macrophages might represent a feasible treatment for chronic cholestatic liver diseases.

MeSH terms

  • Animals
  • Bile Duct Diseases / metabolism
  • Bile Duct Diseases / pathology*
  • Bile Ducts / pathology*
  • Cell Proliferation
  • Chronic Disease
  • Disease Models, Animal*
  • Extracellular Matrix / metabolism*
  • Macrophages / pathology*
  • Mice

Grants and funding

This work was supported by the following sources of funding. JB: Brustem: Impulse program 2011-IP-LS-104–Brustem (Brussels Government); SV: Flemish Government Agency for Innovation by Science and Technology, IWT/SB/121548; LD, LvG, NvH, KL & IAL: Interuniversity Attraction Poles (IAP)—phase VII—contract P7/47 (Federal Science Policy –BELSPO), and Brustem: Impulse program 2011-IP-LS-104–Brustem (Brussels Government). HVV, LvG & LD: Research Foundation Flanders (FWO, grant: G.0333.13N); LvG & LD: (FWO G.0348.13N); WKS: Foundation for Liver Research, UK; AC: Deutsche Forschungsgemeinschaft (DFG, grants 267/4-1; 267/6-1 and 267/8-1) and the Wilhelm Laupitz Foundation.