6533b7d1fe1ef96bd125d522

RESEARCH PRODUCT

Dendritic cells and the handling of antigen

subject

description

Dendritic cells (DC) are a sparsely distributed, migratory group of bone marrow-derived leucocytes that are specialized for the uptake, transport, processing and presentation of antigens to T cells [1,2]. At an immature stage of development DC are considered as the first-line sentinels in immune surveillance of peripheral tissues, including epithelia of the skin and mucosal surfaces, where they sample continuously the antigenic local microenvironment by uptake of self- and exogenous antigen via macropinocytosis/endocytosis [3,4]. The efficiency of DC to initiate an immune response against infectious disease is due to their constant trafficking between peripheral tissues and draining lymph nodes. DC residing in mucocutaneous epithelia are specialized in the uptake and processing of foreign antigen. Upon antigenic stimulation in the presence of inflammatory mediators, DC mature, process antigen and become migratory; they enter secondary lymphoid organs where they use these newly acquired capabilities to induce a T cell-dependent immune response. Following migration to draining lymph nodes, DC acquire expression of co-stimulatory molecules and become efficient at presenting antigenic peptides loaded onto MHC class I and class II molecules to naive CD8 and CD4 T cells, respectively [5].