Immune regulation by CD40-CD40-L interactions - 2; Y2K update

CD40 is a cell surface receptor, which belongs to the TNF-R family, and whi ch was first identified and functionally characterized on B lymphocytes. Ho wever, in recent years it has become clear that CD40 is expressed much broa der, including expression on monocytes, dendritic cells, endothelial cells and epithelial cells. Therefore it is now thought that CD40 plays a more ge neral role in immune regulation. The present paper reviews recent developme nts in this field of research, with main emphasis on CD40 signal transducti on and on in vivo functions of CD40/CD40-L interactions.