The mannose receptor: linking homeostasis and immunity through sugar recognition

The mannose receptor (MR) can potentially internalize compounds that are recognized by three binding sites located in its extracellular region. It is subject to proteolytic processing and glycosylation, has a complex expression pattern and exhibits tissue-dependent binding properties. It is not surprising, given this complexity, that the MR has been implicated in homeostatic processes, such as clearance of endogenous products and cell adhesion, as well as pathogen recognition and antigen presentation. In this Review, we summarize the current knowledge regarding the different aspects of MR binding properties, contribution to homeostatic clearance, cell activation and antigen presentation.