CCL5 and systemic lupus erythematosus: We further checked the DNA methylation status on IL-15 and CCL5, and identified six of 11 methylation sites (cg01856970, cg02934500, cg25546588, cg16655388, cg26269613, and cg20060523) on IL-15, which are located at 5′UTR, TSS1500, and TSS 200 regions, were hypomethylated in both SLE LN+ and SLE LN− patients in relation to NC (Fig. 7c).