Interactions of Adipose and Lymphoid Tissues

Abstract

Interactions between adipose and lymphoid tissues at the molecular, cellular and tissue levels are summarised, with emphasis on the special composition and metabolic properties of perinodal adipose tissue that is anatomically associated with lymph nodes. Perinodal adipose tissue intervenes between the diet and nutrition of the immune system, modulating the action of dietary lipids on immune function. The roles of peptide and lipid-derived messenger molecules are complementary; precursors of prostaglandins and leukotrienes are specific fatty acids that are often dietary essential and may be supplied to lymphoid cells by paracrine interactions with adjacent adipocytes. Prolonged stimulation of paracrine interactions may induce local hypertrophy of adipose depots associated with lymphoid structures. Specialization of adipose tissue for paracrine interactions may be a unique, advanced feature of mammals that supports faster, more efficient immune processes and permits fever and other energetically expensive defences against pathogens to take place simultaneously with immune responses and unrelated functions such as lactation and exercise. The possible roles of local interactions between adipose and other tissues, and defects thereof, in human diseases including HIV-associated lipodystrophy, Crohns disease, lymphedema, atherosclerosis and in obesity and starvation are briefly reviewed.