SPDEF and systemic lupus erythematosus: Obtained model suggested a biomarker panel of 9 antibodies, targeting 8 proteins, i.e., GTP-binding protein Rhes (RASD2), S100A12, SLC22A2, Matrix metalloproteinase-1 (MMP1), CRISP3, complement component C6 (C6), Phospholipid phosphatase 1 (PPAP2A), SPDEF, achieving a ROC AUC of 0.78 (95% CI: 0.73–0.83) for prediction of SLE patients and controls (Figure 2).