CD19 and systemic lupus erythematosus: We found that PBX1 expression in CD19+ B cells was lowest in SLE-DS patients than in SLE patients and healthy donors (Fig. 1A), and the expression of PBX1 in CD19+ B cells negatively correlated with SLEDAI in SLE patients (Fig. 1B), which was also proved by the latest research in 2023.[14] Thus, we speculated that PBX1 might serve as a potential biomarker for the clinical diagnosis and treatment of lupus in patients with demyelinating syndrome.