Unravelling novel functions of the endosomal transporter mannose 6-phosphate/insulin-like growth factor receptor (CD222) in health and disease: An emerging regulator of the immune system.

Properly balanced cellular responses require both the mutual interactions of soluble factors with cell surface receptors and the crosstalk of intracellular molecules. In particular, immune cells exposed unceasingly to an array of positive and negative stimuli must distinguish between what has to be tolerated and attacked. Protein trafficking is one of crucial pathways involved in this labour.