SDF4 is a potential biomarker for diagnosis and severity assessment in patients with systemic lupus erythematosus

Abstract Background The implementation of refined management of systemic lupus erythematosus (SLE) poses a considerable challenge in clinical practice. In this study, we evaluated serum stromal cell-derived factor 4 (SDF4) as potential biomarkers for SLE diagnosis, disease severity, and prognosis. Methods We determined the SDF4 levels in peripheral blood mononuclear cells (PBMC) and serum from patients with SLE using RT-qPCR, Western blot and ELISA, respectively. Spearman’s rank correlation, logistic regression, and ROC curves were employed to assess clinical value of SDF4 in SLE. Results Compared with the healthy control group, the mRNA and protein levels of SDF4 in PBMC of SLE patients significantly upregulated ( P < 0.05), and serum SDF4 concentrations were markedly elevated. Logistic regression analysis showed that increased SDF4 levels were significantly associated with the occurrence of SLE (Z = -6.707, P < 0.001). Notably, ROC curve analysis demonstrated that the area under the ROC curve for serum SDF4 in distinguishing SLE patients from healthy controls was 0.954, with a sensitivity of 95.83% and a specificity of 80.00% at a cut-off value of 43.18 pg/mL. Moreover, the AUC of the ROC curve for combined prediction using serum SDF4 levels and the traditional clinical indicator of anti-dsDNA antibody titer was 0.975. Furthermore, the level of SDF4 was positively correlated with multiple organ injury (arthritis, anemia and so on) in SLE patients. Conclusion Our findings suggest that the serum levels of SDF4 may serve as potential biomarkers for diagnosis and disease evaluation in patients with SLE.