Interleukin-7 in Health and Disease

Abstract

Interleukin-7 (IL-7) mRNA and protein can be detected in both immune and non-immune cells, including bone marrow stroma cells, B-cells, monocytes/macrophages, follicular dendritic cells and in transformed and non-transformed cells of epithelial origin. This multifaceted cytokine plays a central role in lymphopoiesis and in adaptive immune responses. Particularly in infectious diseases, IL-7-mediated effects are dependent on the nature of the infectious agent and the timing of application: IL-7 may exert beneficial or deleterious effects on the host. In cancer, IL-7 may support the expansion of tumor-reactive immune responses. In contrast, IL-7 may also be able to deliver growth signals for transformed cells. Future studies will elucidate whether IL-7 represents a candidate molecule which is able to deliver T-cell survival and maturation in the peripheral circulation as well as in secondary lymphoid tissues.