PTPRC and systemic lupus erythematosus: The numbers and proportions of urinary CD11c+ macrophages among CD45+ cells were specifically and significantly higher in patients with active proliferative LN (SLEDAI 15.2 ± 5.2) than in patients with active SLE (SLEDAI 14.6 ± 5.7) without LN, those with inactive LN (SLEDAI 3.4 ± 0.9), or those with other diseases (i.e., IgA nephropathy and ANCA-associated vasculitis) (Fig. 1a).