Glomerular Proteomic Profiles in the NZB/W F1 Hybrid Mouse Model of Lupus Nephritis

Figure 1. Photomicrographs of the histology of the kidney in the NZB/W F1 hybrid mouse model of mild and severe lupus nephritis shows the renal glomeruli. (A) NZB/W F1 hybrid mouse model. Severe proteinuria (the proteinuria ≥3+ group). (B) NZB/W F1 hybrid mouse model. Mild proteinuria (the proteinuria ≤+ group). (C) C57BL/6 age-matched mouse control group. Images from left to right, hematoxylin and eosin (H&E), magnification ×400; Periodic acid Schiff (PAS), magnification ×400; Masson’s trichrome, magnification ×400. Severe lupus nephritis in the NZB/W F1 hybrid mouse model is shown by glomerular mesangial cell proliferation, sclerosis, nuclear fragmentation and shrinkage (pyknosis), and neutrophil infiltration.

Figure 2. (A–D) Images of the two-dimensional fluorescence difference gel electrophoresis (2D-DIGE). The gels were analyzed using a Typhoon TRIO scanner, which acquired the two-dimensional differential gel electrophoresis image (2D-DIGE). The dyed blue map using Cy2 is the internal standard group, the dyed green map using Cy3 is the severe proteinuria group, the dyed red map using Cy5 is the mild proteinuria group. The last image is the superposition of three fluorescence channels.

Figure 3. Western blot analysis of protein expression in the kidney glomeruli from the NZB/W F1 hybrid mouse model group 1 (mild proteinuria) and group 2 (severe proteinuria). The Western blot images on the left are the mild proteinuria ≤1+ group, and the images on the right are the severe proteinuria ≥3+ group. The expression of Ras-related GTP-binding protein B (RRAGB) and angiopoietin 2 (ANGP2) are upregulated and the expression of serine/threonine-protein kinase 1 (SMG1), methylmalonate semialdehyde (MMSA), and ATP beta chain (ATPB) are down-regulated. The gray value histogram of the Western blot validation results shows that the gray value of the ratio of each control group and the internal control are all 1 on the left side. On the right side, the same pattern is found. The gray values of the corresponding proteins were first compared with internal control and then compared with the base value. * Proteinuria ≥3+ group compared with proteinuria ≤1+ group, P<0.05. ** Proteinuria ≤1+ group compared with proteinuria ≥3+ group, P<0.05.

Figure 4. (A–C) Immunohistochemical of kidney tissue sections in the NZB/W F1 mouse model group 1 (mild proteinuria) and group 2 (severe proteinuria) groups. Angiopoietin 2 (ANGP2) and Annexin A5 (ANXA5) (as the control) expression in the glomeruli are increased in the proteinuria ≥3+ group (group 2) of NZB/W F1 mice, but the expression of methylmalonate semialdehyde (MMSA) in the glomeruli is reduced. The left images show the mild proteinuria group (proteinuria ≤1+), and the right images show the severe proteinuria group (proteinuria ≥3+).