We study how obesity impacts health. The growing worldwide obesity epidemic is frequently linked to hyperlipidemia, inflammation, and insulin resistance leading to increased risk of diabetes and cardiovascular disease. The long-term goal of our laboratory is to determine mechanisms by which obesity increases risk for and pathophysiological consequences of these devastating diseases. Macrophages are part of the innate immune system that infiltrate white adipose tissue (fat) in obese rodents and humans, and produce most of the inflammatory cytokines and chemokines secreted from adipose tissue. In addition, their presence has been shown to be temporally associated with the development of insulin resistance. Our current research focus is threefold: to determine mechanisms by which macrophages accumulate in adipose tissue, to determine the role of resident macrophages in normal adipose tissue function, and to determine how other immune cells like eosinophils also contribute to adipose tissue function.