INS and obesity due to melanocortin 4 receptor deficiency: In brief, expanded adipose tissue in obesity recruits immune cells that contribute to a chronic state of low-grade inflammation and dysregulated metabolism.10 11 Macrophages are key mediators of inflammation and insulin resistance in obesity.12 13 In adipose tissue of obese individuals, macrophage populations switch from anti-inflammatory, homeostasis maintaining cells towards a more proinflammatory phenotype with insulin desensitizing actions.