CD40 and systemic lupus erythematosus: We further analyzed in a second cohort of SLE patients (cohort 2), the majority having a LN flare (Supplementary Table 2), the intrinsic expression levels of distinctive surface markers on monocyte-derived non-activated macrophages (M0) (CD64) or monocyte-derived immature DCs (iDC) (CD83, CD86, CD80, CD40, and HLA-DR).