CD4 and systemic lupus erythematosus: To further investigate the role of immune cell infiltration in SLE-APO, we performed a comprehensive evaluation using CIBERSORT and conducted correlation analysis between infiltrating immune cells and SEZ6, NRAD1, and LPAR4. The SLE-APO group exhibited a significantly higher proportion of plasma cells (P < 0.05) and naïve CD4+ T cells (P < 0.01), and a significantly lower proportion of monocytes (P < 0.01) than the SLE-NC group.