The increased levels of uIL-5 can justify the appearance of eosinophils and ECP in urine of the SLE patients studied because the cytokine IL-5, which is a key Th2 cytokine in eosinophil biology, is involved in eosinophil differentiation, maturation, migration and activation of these cells [37]. This evidence concerns the gene RNASE3 and systemic lupus erythematosus.