However, it is currently well appreciated that IL-6 is a pleiotropic cytokine, and it has both pro-inflammatory and anti-inflammatory effects, with complex roles in inflammation and metabolic disease. For instance, it has been recently described that IL-6 is constitutively expressed by human beta and alpha cells, suggesting a physiological role for this cytokine within the islets (167). The gene discussed is IL6; the disease is metabolic disease.