TNFSF13B and systemic lupus erythematosus: Cytokines with diverse effects on the immune system such as IL-6 [14-17], B cell activating factor of the tumour necrosis factor family (BAFF), and macrophage migration inhibitory factor (MIF) have each been shown to have some interplay with IL-17 [18,19], and to have potential roles in the pathogenesis or clinical expression of SLE [2,20].