Figure 1.

High mobility group B1 (HMGB1) regulation during fibrosis and validation and characterization of macrophage‐specific deletion of HMGB1. Representative immunoblotting against HMGB1 in oil (n = 9) or CCL₄‐treated (n = 15) liver using glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) protein as a loading control (A). Representative immunoblotting against HMGB1 in liver extracts from sham (n = 9) or BDL (n = 4) animals using GAPDH protein as a loading control (B). Peritoneal macrophages isolated from HMGB1^Flox (n = 3) and HMGB1^ΔMac mice (n = 3) were analyzed by immunoblotting against HMGB1 and GAPDH (C). Cells from liver stromal vascular fraction, isolated from HMGB1^ΔMac and HMGB1^Flox mice, were analyzed by immunoblotting against HMGB1 and GAPDH (D). Cells from lung stromal vascular fraction, isolated from HMGB1^Flox (n = 3) and HMGB1^ΔMac mice (n = 3), were analyzed by immunoblotting against HMGB1 and GAPDH (E). Bone marrow‐derived macrophages (BMDM) isolated from HMGB1^Flox (n = 3) and HMGB1^ΔMac mice (n = 3) were analyzed by immunoblotting against HMGB1 and GAPDH (higher panel). BMDM isolated from HMGB1^Flox and HMGB1^ΔMac mice were analyzed by immunofluorescence confocal microscopy to detect HMGB1 (red) while nuclei were stained with DAPI (blue) (lower panel). Scale bar: 5 μm (F). Liver extracts of HMGB1^Flox (n = 9) and HMGB1^ΔMac (n = 6) mice were analyzed by western blotting directed against α‐smooth muscle actin (α‐SMA) (G). Representative images of liver fibrosis determined by picosirius Red staining from HMGB1^Flox (n = 9) and HMGB1^ΔMac (n = 6) mice. Scale bar: 500 μm (H). Representative images of myofibroblast activation determined by α‐SMA immunostaining from HMGB1^Flox (n = 9) and HMGB1^ΔMac (n = 6) mice liver sections. Scale bar: 500 μm (I)