Related Experiment Video
Updated: Jun 17, 2026
05:47
Isolation and Transplantation of Different Aged Murine Thymic Grafts.
Published on: May 13, 2015
The effect of age on the phenotype and function of developing thymocytes
1Infection & Immunity and Genes & Development Group, Department of Veterinary Basic Sciences, Royal Veterinary College, London, UK.
Journal of Comparative Pathology
|December 17, 2009
Summary
Aging impairs the immune system, particularly T-cell development in the thymus. Older mice showed flawed thymocytes, impacting immune response and contributing to immunosenescence.
Area of Science:
- Immunology
- Gerontology
- Cell Biology
Background:
- Immune system decline with age (immunosenescence) is linked to thymic involution.
- Mechanisms of age-associated thymic involution and its impact on T-cell development are not fully understood.
Purpose of the Study:
- To investigate the effects of aging on T-cell development and thymopoiesis in mice.
- To identify molecular and functional changes in thymocytes during aging.
Main Methods:
- Studied thymopoiesis in mice aged 1 to 18 months.
- Analyzed thymic cellularity, thymocyte subset proportions, and expression of molecules like CD3 and CD24.
- Assessed thymocyte response to mitogens, activation marker (CD69) expression, cell cycle progression, and apoptosis resistance.
Main Results:
- Thymic cellularity decreased with age, with significant loss early in life.
- Expression of CD3 and CD24 declined in thymocytes from older mice.
- Older mice thymocytes showed reduced response to mitogens, impaired CD69 upregulation, and increased resistance to apoptosis.
Conclusions:
- T cells may be intrinsically flawed before leaving the thymus in aged individuals.
- These thymocyte defects likely contribute to the age-associated decline in immune function and increased susceptibility to infections.
Related Concept Videos
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...
01:16Primary Lymphoid Organs
Primary lymphoid organs are pivotal in the formation, development, and maturation of lymphocytes, the white blood cells that serve as the backbone of our immune system. This crucial function underscores their fundamental role in maintaining our overall health and immunity. The two primary lymphoid organs of prime importance are the red bone marrow and the thymus.
The red bone marrow is a soft, spongy tissue nestled in the interior of long bones such as the humerus and femur. It is the site...
The red bone marrow is a soft, spongy tissue nestled in the interior of long bones such as the humerus and femur. It is the site...
01:18Functions of Thyroid Hormones
The thyroid hormone (TH) plays a pivotal role in the intricate orchestration of physiological processes, exerting profound effects on development, metabolism, and homeostasis throughout different life stages.
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...
01:22Development of Immunocompetence
The initiation of cell-mediated immunity can be observed as early as the third month of fetal growth, with active antibody-mediated immunity following approximately one month later.
The initial cells that migrate from the fetal thymus settle within the skin and epithelial tissues lining the mouth, digestive tract, and in females, the uterus and vagina. These cells, including skin-based dendritic cells, serve as antigen-presenting cells, playing a key role in T cell activation.
Subsequent T...
The initial cells that migrate from the fetal thymus settle within the skin and epithelial tissues lining the mouth, digestive tract, and in females, the uterus and vagina. These cells, including skin-based dendritic cells, serve as antigen-presenting cells, playing a key role in T cell activation.
Subsequent T...
01:22Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Absorption
As individuals age, their body's physiology evolves, affecting drug pharmacokinetics. The most apparent changes occur in the gastrointestinal tract, where an increase in gastric pH, a delay in gastric emptying, and a reduction in gastrointestinal motility are observed. Remarkably, these changes do not substantially modify the absorption of orally administered drugs, particularly those absorbed via passive diffusion.Transdermal drug delivery emerges as a highly viable method for older adults due...
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...