The brain and thymus have much in common: a functional analysis of their microenvironments

Research into the neural and immune systems has began to converge. Since th e first reports that interleukins play important roles in both systems and that lymphocytes secrete neuronal factors, scientists have been surprised b y the ever-increasing list of interactions. Here, Rolf Mentlein and Marion Kendall examine the major supporting cells of the brain and thymus - astroc ytes and thymic epithelial cells - the similar neuroectodermal origin of wh ich could explain such fundamental analogies.