Aging and T-cell-mediated immunity.
1Department of Medicine and Center on Aging, University of Rochester Cancer Center, University of Rochester Medical Center, NY 14642, USA.
Mechanisms of Ageing and Development
|July 16, 1999
Summary
Aging significantly impairs T-cell immunity through complex cellular and molecular changes. This review explores age-related T-cell deficiencies, paradoxes, and potential therapeutic strategies for enhancing immune function in older adults.
Area of Science:
- Immunology
- Gerontology
- Cellular Biology
Background:
- Immunological aging is characterized by a decline in T-cell-mediated immunity.
- This decline is multifactorial, affecting T-cell subsets and activation pathways.
- Thymic involution and intrinsic/extrinsic factors contribute to age-related T-cell immune deficiency.
Purpose of the Study:
- To review the cellular and molecular aspects of age-related T-cell immunodeficiency.
- To discuss paradoxes in T-cell-mediated immunity during aging.
- To suggest experimental approaches and therapeutic interventions for enhancing immune function in the elderly.
Main Methods:
- Review of current scientific literature on immunosenescence.
- Analysis of cellular and molecular mechanisms underlying T-cell dysfunction with age.
- Exploration of the roles of monocytes and macrophages in age-related immune changes.
Main Results:
- Age-related changes impact T-cell composition, protein tyrosine phosphorylation, calcium mobilization, and protein kinase C translocation.
- Lymphocyte proliferation and cytokine production are diminished in aged individuals.
- The function of monocytes and macrophages in T-cell activation is altered with age.
Conclusions:
- Age-related T-cell immune deficiency is a complex process involving multiple cellular and molecular alterations.
- Understanding these changes may reveal therapeutic targets to restore immune function in the elderly.
- Further research is needed to resolve controversies and develop effective interventions.
Related Concept Videos
01:40Cell-mediated Immune Responses
Overview
01:19The Effect of Aging on Tissues
Several body functions deteriorate with age. The external signs of aging are easily identifiable. For example, the skin becomes dry, less elastic, and thins out, forming wrinkles. The skin of the face begins to appear looser due to a decrease in the levels of elastic and collagen fibers in the connective tissue. Additionally, melanin production in the hair follicle decreases with age, resulting in gray hair. Moreover, the senses of sight and hearing decline, so glasses and hearing aids may...
01:20Special Features of Adaptive Immunity
The adaptive immune system, a crucial component of the overall immune response, offers a highly specialized defense against pathogens. It involves specific cell types and features, enabling it to combat infections effectively and efficiently.
The primary cell types involved in adaptive immunity are T cells and B cells. Each type has a unique role in defending the body against pathogens. T cells are responsible for cell-mediated immunity. They identify and eliminate infected cells directly,...
The primary cell types involved in adaptive immunity are T cells and B cells. Each type has a unique role in defending the body against pathogens. T cells are responsible for cell-mediated immunity. They identify and eliminate infected cells directly,...
01:23Cells of the Adaptive Immune Response
The T and B lymphocytes of the adaptive immune system develop from common lymphoid progenitor cells in the bone marrow. These progenitors give rise to precursors that eventually develop into both T and B lymphocytes. As these precursors mature, they gain the ability to detect and respond to foreign antigens in the body, a process known as immunocompetence. Additionally, these precursors acquire self-tolerance, a process that ensures they do not react to self-antigens. This intricate system...
01:22T 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...
Naive T cells that have not yet encountered an antigen express two primary CD...
01:24T 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...
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...