reported that PD-1 staining was detected in the glomeruli in 8 of 13 samples from patients with lupus nephritis compared with 0 of 9 control samples; similarly, PD-1 was detected in renal tubules in 6 of 13 samples from patients with lupus nephritis but in 0 of 9 control samples; all 8 PD-1+ lupus nephritis samples were also stained positive for CD3 expressed in the glomeruli and tubulointerstitial region, suggesting a correlation between PD-1 and CD3+ T cell infiltrates in lupus nephritis (106). This evidence concerns the gene PDCD1 and lupus nephritis.