We have performed a literature search and provide a brief summary on the cytokines and free radicals (IFN-γ, GM-CSF, IL-5, IL-17F, IL-18, IL-21, VEGF, LPO and CAT) that are significantly correlated with HLA-DRB1*04 allele in Malay SLE patients together with the evidence gathered from a number of previously published studies that depicted the involvement of these cytokines and free radicals in SLE and LN pathogenesis (Table 6). This evidence concerns the gene IL21 and systemic lupus erythematosus.