In contrast, peritoneal exudate cells (PEC) from mice treated with mineral oil (MO), an inflammatory hydrocarbon that does not cause lupus, are progressively enriched in a subset of anti-inflammatory CD11b+F4/80+CD138+ Mφ reminiscent of alternatively activated (M2) Mφ (6). This evidence concerns the gene SDC1 and systemic lupus erythematosus.