Fig. 6

Mesangial cell proliferation induced by platelet-derived growth factor-B (PDGF-B) from blood cells of systemic lupus erythematosus (SLE) patients. Mesangial cells were serum starved for 24 h and then stimulated for 4 h with culture medium from blood cells of SLE patients (a; N _SLE = 8) stimulated with 500 nM CpG. Mesangial cells were serum starved for 24 h and then stimulated for 20 h with plasma from SLE patients (b; N _SLE = 13) or healthy controls (b; N _Control = 13) in culture medium. Mesangial cells were serum starved for 24 h and then stimulated for 20 h with plasma from SLE patients (c; N _SLE = 6), with anti-PDGF-B neutralizing antibody (1 or 10 μg/ml) or control antibody (1 or 10 μg/ml) added. Proliferation was measured by MTT assay. The results are presented as mean and SEM