Related Experiment Video
Updated: Sep 28, 2026

Purification of the Membrane Compartment for Endoplasmic Reticulum-associated Degradation of Exogenous Antigens in Cross-presentation
Published on: August 21, 2017
Cross-presentation of cell-associated antigens by CD8alpha+ dendritic cells is attributable to their ability to
Oliver Schulz1, Caetano Reis e Sousa
1Immunobiology Laboratory, Cancer Research UK, London Research Institute, Lincoln's Inn Fields Laboratories, 44 Lincoln's Inn Fields, London WC2A 3PX, UK.
In the mouse, cross-presentation is an exclusive property of the CD8alpha+ subset of dendritic cells (DC) but the basis for this selectivity remains unclear. Here we report that splenic CD8alpha+ DC are much superior to other DC subsets in internalizing dying cells in vitro. In contrast, CD8alpha+, CD8alpha- CD4+ and CD8alpha- CD4- DC subsets phagocytose bacteria or latex beads to a similar extent. Although CD8alpha+ DC are better than CD4+ DC at presenting ovalbumin (OVA)-loaded splenocytes to naïve OT-I T lymphocytes, CD4+ DC are better at presenting OVA-expressing Escherichia coli to the same T cells. In both cases, presentation is abrogated by lactacystin. These results show that both splenic CD8alpha+ and CD8alpha- DC can present exogenous antigens on major histocompatibility complex (MHC) class I via a proteasome-dependent pathway and suggest that the specialized cross-presenting function of CD8alpha+ DC is a result of their ability to endocytose dying cells rather than a unique pathway for handling endosomal contents.
In the mouse, cross-presentation is an exclusive property of the CD8alpha+ subset of dendritic cells (DC) but the basis for this selectivity remains unclear. Here we report that splenic CD8alpha+ DC are much superior to other DC subsets in internalizing dying cells in vitro. In contrast, CD8alpha+, CD8alpha- CD4+ and CD8alpha- CD4- DC subsets phagocytose bacteria or latex beads to a similar extent. Although CD8alpha+ DC are better than CD4+ DC at presenting ovalbumin (OVA)-loaded splenocytes to naïve OT-I T lymphocytes, CD4+ DC are better at presenting OVA-expressing Escherichia coli to the same T cells. In both cases, presentation is abrogated by lactacystin. These results show that both splenic CD8alpha+ and CD8alpha- DC can present exogenous antigens on major histocompatibility complex (MHC) class I via a proteasome-dependent pathway and suggest that the specialized cross-presenting function of CD8alpha+ DC is a result of their ability to endocytose dying cells rather than a unique pathway for handling endosomal contents.
Related Concept Videos
T Cell Activation and Clonal Selection
Naive T cells that have not yet encountered an antigen express two primary CD...
Antigen Presenting Cells
T cells require the help of antigen-presenting cells (APCs), which process foreign antigens into smaller fragments that can be recognized by T cells. These APCs are highly specialized cells that efficiently internalize antigens...
Antigens Involved in Adaptive Immunity
Complete Antigens
Complete antigens possess both immunogenicity and reactivity.
Cytotoxic T Cells-mediated Immune Response
Immunological surveillance is the ability of immune cells to monitor and eliminate infected cells with intracellular pathogens, neoplastically transformed cells, and cells with non-self antigens. Cytotoxic T cells and NK...
Phagocytosis of Apoptotic Cells
Normal cells contain receptors that prevent them from being recognized by phagocytes.
Cell-mediated Immune Responses

