INS and type 2 diabetes mellitus: Increased infiltration of macrophages and other immune cells in the adipose tissue, liver, muscle, and pancreas in T2DM patients can stimulate the production of proinflammatory factors, interfere with the insulin signaling in peripheral tissues, or induce β cellular dysfunction and subsequent insulin deficiency, which leads to the development of T2DM (Ehses et al., 2009; Donath and Shoelson, 2011; Esser et al., 2014).