Optimal induction of effector but not memory antitumor cytotoxic T lymphocytes involves direct antigen presentation

Y Guilloux1, X F Bai, X Liu

  • 1Department of Pathology and Comprehensive Cancer Center, Ohio State University Medical Center, Columbus 43210 USA.

Cancer Research
|February 28, 2001
PubMed

MHC class I-restricted tumor antigen can be presented to CD8+ T cells by two distinct mechanisms. Direct presentation involves degradation of cytosolic proteins by the proteosome into peptides, transport of the peptides across the endoplasmic reticulum membrane, and expression of the MHC-peptide complex on the tumor cell surface. Cross-presentation, on the other hand, involves uptake and intracellular processing of the tumor antigen by host antigen-presenting cells. Whereas it is clear that cross-presentation is necessary and sufficient for the induction of memory CTLs, it has not been tested whether such presentation is sufficient to induce effector CTLs. Here we analyzed the requirements of direct antigen presentation for the induction of effector and memory antitumor CTLs using a MHC class I- mutant incapable of direct antigen presentation and its parent, the MHC class I+ J558 cell line. We report that in comparison with the MHC class I+ tumor cell, the MHC class I- mutant induces equal priming for recall CTL response but poor effector CTLs. Our results demonstrate that optimal induction of effector CTLs, but not memory CTLs, requires direct antigen presentation by the tumor cells.

Related Concept Videos

Cytotoxic T Cells-mediated Immune Response01:27

Cytotoxic T Cells-mediated Immune Response

Cytotoxic T cells are a vital component of the immune system. They have the remarkable ability to identify and target antigens on infected or abnormal cells. These antigens often originate from intracellular pathogens such as viruses or abnormal proteins cancer cells produce.
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...
T Cell Activation and Clonal Selection01:22

T Cell Activation and Clonal Selection

T cells are integral to our adaptive immune system, recognizing and effectively responding to foreign antigens. T cell activation and clonal selection are pivotal in orchestrating this immune response. This article elucidates these mechanisms, detailing the roles of cluster of differentiation (CD) markers, major histocompatibility complex (MHC) molecules, costimulatory signals, and the process of clonal selection.
Naive T cells that have not yet encountered an antigen express two primary CD...
Tumor Immunotherapy01:27

Tumor Immunotherapy

Immunotherapy is a treatment that boosts or manipulates the immune system to fight diseases, including cancer. For instance, by stimulating an immune response through vaccinations against viruses that cause cancers, like hepatitis B virus and human papillomavirus, these diseases can be prevented. Nonetheless, some cancer cells can avoid the immune system due to their rapid mutation and division. The immune response to many cancers involves three phases: elimination, equilibrium, and escape.
Cell-mediated Immune Responses01:40

Cell-mediated Immune Responses

Overview
T Cell Types and Functions01:24

T Cell Types and Functions

When T cells with CD4 markers are activated, they give rise to two types of effector cells: helper T cells and regulatory T cells. Meanwhile, T cells with CD8 markers differentiate into effector cytotoxic T cells. The differentiation of CD4 T cells into helper T cell subsets, such as Th1, Th2, and Th17 cells, is dependent on the antigen type, antigen-presenting cell, and regulatory cytokines.
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
Antigens Involved in Adaptive Immunity01:26

Antigens Involved in Adaptive Immunity

An antigen is any substance the immune system identifies as foreign and potentially harmful to the body, prompting an immune response. Antigens have two functional properties: immunogenicity and reactivity. Immunogenicity is the ability of an antigen to stimulate a specific immune response. At the same time, reactivity describes the antigen's ability to react with the cells and antibodies produced in response to it.
Complete Antigens
Complete antigens possess both immunogenicity and reactivity.