CD86 and systemic lupus erythematosus: Valproic acid (VPA) exhibits various effects in different environments: it promotes M2 polarization of macrophages under normal conditions, suppresses M1 cell surface biomarker CD86 expression in systemic lupus erythematosus (SLE)-derived macrophages, and selectively induces macrophages to polarize toward the M2 phenotype in normal tissues, thereby exerting an interventional effect on tumor growth and a protective effect on normal tissues [33,34].