The Subcellular Compartment for Endoplasmic Reticulum-Associated Degradation of Exogenous Antigens from dendritic cells

Abstract

Dendritic cells (DCs) have the unique ability of processing and presenting exogenous antigens upon major histocompatibility class I (MHC I) molecules. This ability is called antigen cross-presentation (CP) and plays not only in the activation of naive CD8 + T into anti-infectious and anti-tumoral cytotoxic CD8 + T cells, but also in the inactivation of self-acting naive T cells by T cell anergy or T cells deletion. Since antigen CP was first described more than four decades ago, so many numbers of studies, by using a variety of sources of antigens and antigen-presenting cells (APCs), had been carried out to solve the cellular process of CP. There are accumulating in vivo and in vitro evidences that endoplasmic reticulum (ER)-associated degradation (ERAD) acts as a key player in CP. But for all these efforts, the precious molecular mechanisms for CP are still remained to be elucidated. It may be partially because there are several pathways for CP running alongside with each other and each cell uses these several pathways redundantly responding against environmental conditions. Here, we review the intracellular transport routes for exogenous antigens and the subcellular compartment in which exogenous antigens undergo ERAD.