Hardy and his colleagues demonstrated not only that five genes including CCL2, CCL3, CCL4, CCL18 and IL8/CXCL8 were most highly expressed independent of body mass index (BMI) in the human omental adipose tissue of insulin-resistant obese (IRO) subject, as compared with insulin-sensitive obese (ISO) subjects, but that increased macrophage infiltration in the omental adipose tissue was correlated to insulin resistance. This evidence concerns the gene CCL2 and Insulin resistance.