Catalog no c1005

After fixing cells in 4% paraformaldehyde for 20 minutes (Cat. No. P0099-100 ml, Beyotime), they were incubated in TritonX-100 (Catalog No. P0099-100 ml, Beyotime) for 10 minutes at room temperature and then closed in 5% BSA (Catalog No. ST025-5 g, Beyotime). The samples were then conjugated with anti-CD68 antibodies (Catalog No. ab955, abcam, 1:200), anti-CD86 antibodies (Catalog No. 13395–1-AP, Proteintech, 1:200), and anti-CD206 antibodies (Catalog No. 18704–1-AP, Proteintech, 1:200) and left overnight at 4 °C. Incubate for 1 hour at room temperature with anti-rabbit or anti-mouse IgG. Label the nuclei with DAPI Staining Solution (Catalog No. C1005, Beyotime), then seal the slices with Antifade Mounting Medium (Catalog No. P0126-25 ml, Beyotime) and photographed using fluorescence microscopy (Nikon, Japan).

Immunofluorescence staining was performed on 3 µm paraffin-embedded sections of the kidneys and spleens from 14-week-old lupus mice. The sections underwent dewaxing and hydration steps, followed by heat-mediated antigen retrieval using either sodium citrate (10 mM, pH 6; Catalog No. P0083, Beyotime, Shanghai, China) or Tris–EDTA (10 mM Tris, 1 mM EDTA, pH 9; Catalog No. C1038, Solarbio, Beijing, China, G1480) via microwave for 20 min. To block nonspecific antigens, 5% bovine serum albumin (BSA) was used. Primary antibodies were incubated overnight at 4 °C, while fluorescent secondary antibodies were incubated for 1 h at room temperature. A diluted DAPI solution (1:3 dilution; Catalog No. C1005, Beyotime, Shanghai, China) was applied for 10 min to stain the cell nuclei. After washing with PBS, the sections were sealed using anti-fluorescence quenching sealed tablets. The primary antibodies, fluorescent primary antibodies, and secondary antibodies used for immunofluorescence staining can be found in Additional file 2: Table S1. Immunofluorescence images of the kidneys were acquired using a laser scanning confocal microscope (Leica TCS SP5) and analyzed with Leica LAX software (Leica, Wetzlar, Germany). Immunofluorescence images of spleen T cells and B cells were obtained using an Olympus VS200 fluorescence microscope and analyzed with OlympusVIA software (Olympus, Japan).