Fig. 2: Hepatic PirB is mainly expressed in monocyte-derived macrophages (MDMs).

a PirB mRNA expression in different tissues (n = 4). b, c Flow cytometry (FCM) and quantification of hepatic cells in the livers of the indicated mice (n = 6 mice/group). d PirB mRNA expression in different hepatic cells (n = 3). e Flow cytometry (FCM) of hepatic macrophages of the indicated groups. f Flow cytometry (FCM) of PirB⁺ cells of the livers. In the PirB⁺ CD45⁺ fraction, MDMs accounted for 43.8% (ND) and 77.5% (CDHFD). g Immunocytochemistry staining of Flag-targeted ANGPTL8 and PirB on MDMs and KCs treated with exogenous rA8. h Immunoprecipitation and western blot analyses showing the binding of flag-targeted A8 to PirB on MDMs. i In vitro GST pulldown assay to examine the interaction between ANGPTL8 and the PirB ectodomain. Scrambled PirB ectodomain and scrambled A8 were used as control (ctr). j Upper: Schematic of ANGPTL8 protein. LPLi: region inhibiting lipoprotein lipase (LPL) activity; Middle: amino acid sequences of ANGPTL8 in 77 mammalian species. The shades of blue indicate the degree of similarity, where dark blue indicates high similarity (16–55 and 130–198). Lower: Five mutant ANGPTL8 proteins (Mut1-5). k GST pulldown showing the interaction between mutant ANGPTL8 and the PirB ectodomain. l Binding models predicted by molecular docking and WebLogo plots of the potential binding region. m mRNA expression of cytokines in different hepatic cells treated with rA8 (n = 6). Scale bar, 10 µm. The data are shown as the mean ± s.e.m. and were statistically analyzed by two-tailed Student’s t test. All samples are biologically independent replicates and n indicates the number of biologically independent samples examined. Data shown are representative of three independent experiments with similar results (g–I, k). Uncropped blots are provided in Source Data. All the p values were two-sided. kD relative molecular weight in kilodalton, ND normal diet, CDHFD choline-deficient high-fat diet, MDMs monocyte-derived macrophages, KCs Kupffer cells, Nets neutrophil, HSCs hepatic stellate cells, rA8 recombinant ANGPTL8 protein, IP immunoprecipitation, IB immunoblotting, Mut mutant. Source data are available as a Source Data file.