PTGDS and diabetic kidney disease: In conclusion, we identified 11 immune-related biomarkers for DKD, including 2 up-regulated DEIRGs (CCL19, IL7R) and 9 down-regulated DEIRGs (GHR, FGF1, FYN, VEGFA, F2R, TGFBR3, PTGDS, FGF9, SEMA5A) by bioinformatics analysis.