Why do dendritic cells cross-presentation?

Limited proteolysis in the endocytic compartments of dendritic cells (DCs) favours cross-presentation by preventing the destruction of internalized antigens. In the cytosolic pathway, exogenous antigens are translocated from endosomal compartments into the cytosol for degradation by the proteasome.

What is the purpose of cross-presentation?

Antigen cross-presentation enables dendritic cells (DCs) to present extracellular antigens on major histocompatibility complex (MHC) I molecules, a process that plays an important role in the induction of immune responses against viruses and tumors and in the induction of peripheral tolerance.

What cells are capable of cross-presentation?

It is increasingly clear that not only DCs and macrophages can cross-present antigens, but also many other endocytic cell types are capable of cross-presentation, including monocytes (70, 71), B cells (72), neutrophils (73), and endothelial cells (74).

What is cross priming in immunology?

“Cross-priming” refers to the activation of naive CD8+ T cells by antigen-presenting cells that have acquired nominal antigens from another cell.

What is cross-presentation in dendritic cells?

Cross-presentation is the ability of certain professional antigen-presenting cells (mostly dendritic cells) to take up, process and present extracellular antigens with MHC class I molecules to CD8 T cells (cytotoxic T cells).

How do dendritic cells cross present antigens?

Cross-presentation of cell-associated antigens by MHC class I in dendritic cell subsets. Dendritic cells (DCs) have the unique ability to pick up dead cells carrying antigens in tissue and migrate to the lymph nodes where they can cross-present cell-associated antigens by MHC class I to CD8+ T cells.

What is cross-presentation dendritic cells?

What is a dendritic cell?

Dendritic cell. Dendritic cells in skin. Artistic rendering of the surface of a human dendritic cell illustrating sheet-like processes that fold back onto the membrane surface. When exposed to HIV, some researchers believe that these sheets entrap viruses in the vicinity and focus them to contact zones with T cells targeted for infection.

Can dendritic cells cross-present model antigens in vivo?

Although various types of APC can cross-present model antigens in vitro, most studies indicate that dendritic cells (DCs) are the main cross-presenting APCs in vivo 1. It is still unclear, however, which DC subtypes can or cannot cross-present antigens, in particular under specific inflammatory situations.

How do dendritic T cells cross-activate?

The activation of cross presenting dendritic cells is dependent on stimulation by CD4+ T helper cells. The co-stimulatory molecule CD40/CD40L along with the danger presence of an exogenous antigen are catalysts for dendritic cell licensing, and thus the cross presentation and activation of naive CD8+ cytotoxic T cells.

What is the role of dendritic cells in peripheral tolerance?

In regard to peripheral tolerance, peripheral tissue resting dendritic cells are able to promote self tolerance against cytotoxic T cells that have an affinity for self peptides.