CCL2 and type 1 diabetes mellitus: Another research like Guan et al. studied the levels of specific cytokines like MCP-1 and showed low levels of it in patients with T1DM compared with healthy controls [23]. Similarly, El Samahi et al. studied the levels of intracellular enzyme visfatin in patients with T1DM, showing lower levels compared with healthy controls [24]. All of this information demonstrates that the low levels of cytokine, enzyme, proteins, etc. may play a protective role in the pathogenesis of T1DM and CD.