INS and Insulin resistance: It is known that the adipose tissue of obese mice and humans is characterized by an accumulation of macrophages and, it is thought, that this is a necessary component of disease progression.1–3 The secretion of cytokines tumor necrosis factor-α and interleukin (IL)-6 by infiltrating macrophages are thought to play a direct role in reducing the insulin sensitivity of regional adipocytes.4–6 Even more compelling, the role of the immune system in insulin resistance is no longer thought to be restricted to just the innate arm, but also includes an adaptive immune response.