24 or 96 well plates

Male B6 mice (6-8 weeks old) were purchased from Zhejiang Province Experimental Animal Center (Zhejiang, China). CD209a knockout mice on B6 background (6-8 weeks old) were purchased from the Mutant Mouse Resource Regional Center. The total number of wild type mice used for cell culture was 196, and the number of CD209a knockout mice used was 8. For peritoneal macrophage isolation, mice were injected intraperitoneally with 2 mL thioglycollate broth to elicit peritoneal macrophages. Four days later, cells were collected by lavaging the peritoneal cavity with ice-cold RPMI-1640 medium. The isolated cells were then washed and resuspended in RPMI-1640 supplemented with 10% (v/v) heat-inactivated fetal bovine serum (FBS; Invitrogen, Shanghai, China), 2 mM glutamine, 100 U/mL penicillin, and 100 mg/mL streptomycin. Cells were seeded (in triplicates) at a density of 1 x 10 6 /mL on 24-or 96-well plates (Corning, Acton, MA, USA), and allowed to adhere for 2 h at 37°C under 5% CO 2 . Cells were then washed twice to remove non-adherent cells, supplied with fresh medium as described above, and allowed to rest for 18-24 h. Recombinant mouse LECT2 proteins were generated from Chinese hamster ovary cells, as previously described (Lu et al., 2013) (link). In all experiments, 5 mg/mL LECT2 was used for treatment.