SELPLG and systemic lupus erythematosus: ACR: American College of Rheumatology; SLEDAI: Systemic Lupus Erythematosus Disease Activity Index; SRI-4: Systemic Lupus Erythematosus Responder Index 4; Treg: Regulatory T cells; TFH: Follicular helper T cells; TH17; T helper 17 cells; BILAG: British Isles Lupus Assessment Group index; PGA: Physician's Global Assessment; CLA+: Cutaneous lymphocyte antigen-positive.