After culture with GM-CSF + IL-4 + TNF-α, the MDDCs induced by the SLE serum showed reduced expression of HLA-DR (P < 0.05), CD80 (P < 0.05) and CD86 (P > 0.05) in an IL-10 dose-dependent manner compared with those induced by the normal serum alone. This evidence concerns the gene CD80 and systemic lupus erythematosus.