Related Experiment Video

Updated: Oct 13, 2026

Generation of Orthotopic Pancreatic Tumors and Ex vivo Characterization of Tumor-Infiltrating T Cell Cytotoxicity
06:16

Generation of Orthotopic Pancreatic Tumors and Ex vivo Characterization of Tumor-Infiltrating T Cell Cytotoxicity

Published on: December 7, 2019

Sex steroids induce apoptosis of CD8+CD4+ double-positive thymocytes via TNF-alpha

J A Guevara Patiño1, M W Marino, V N Ivanov

  • 1Immunology Program, Memorial Sloan-Kettering Cancer Center, New York 10021, USA.

European Journal of Immunology
|September 29, 2000
PubMed

Insights

Testosterone triggers thymus cell death by increasing TNF-alpha, a key mediator. This finding offers new ways to manage T cell production issues related to sex hormone imbalances.

Area of Science:

  • Immunology
  • Endocrinology

Background:

  • Thymic T cell production declines post-puberty, potentially due to sex steroids.
  • Sex steroids are known to influence thymic cellularity, with excess causing reduction and depletion causing increase.

Purpose of the Study:

  • To investigate the role of testosterone in thymocyte apoptosis.
  • To elucidate the mechanism by which testosterone affects thymic cellularity, specifically focusing on T cell development.

Main Methods:

  • Investigated the effect of testosterone on CD8+CD4+ double-positive (DP) thymocytes.
  • Utilized anti-TNF-alpha monoclonal antibodies and TNF-alpha knockout (TNF-alpha-/-) models in vivo.
  • Assessed testosterone's impact on TNF-alpha production and DP thymocyte sensitivity to TNF-alpha.

Main Results:

  • Testosterone specifically induces apoptosis in DP thymocytes through TNF-alpha.
  • Anti-TNF-alpha antibodies blocked testosterone-induced DP apoptosis.
  • DP thymocytes from TNF-alpha-/- mice showed resistance to testosterone-mediated apoptosis.

Conclusions:

  • TNF-alpha is the critical mediator of testosterone-induced thymocyte apoptosis.
  • Targeting TNF-alpha presents a potential therapeutic strategy for modulating T cell production in sex hormone-related disorders.

More Related Videos

Identification of Mediators of T-cell Receptor Signaling via the Screening of Chemical Inhibitor Libraries08:49

Identification of Mediators of T-cell Receptor Signaling via the Screening of Chemical Inhibitor Libraries

Published on: January 22, 2019

Real Time Detection of In Vitro Tumor Cell Apoptosis Induced by CD8+ T Cells to Study Immune Suppressive Functions of Tumor-infiltrating Myeloid Cells09:57

Real Time Detection of In Vitro Tumor Cell Apoptosis Induced by CD8+ T Cells to Study Immune Suppressive Functions of Tumor-infiltrating Myeloid Cells

Published on: January 29, 2019

Related Concept Videos

The Extrinsic Apoptotic Pathway01:17

The Extrinsic Apoptotic Pathway

The extrinsic apoptotic pathway is initiated when extracellular death-inducing signals, such as specific cytokines, activate the death receptors expressed on the cell surface. The immune cells involved in this pathway are natural killer cells (NK cells) and cytotoxic T-lymphocytes. NK cells are critical in innate immune response, while cytotoxic T-lymphocytes are associated with adaptive immune response. These cells recognize specific receptors expressed on the altered cells and activate...
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...
Apoptosis01:30

Apoptosis

Apoptosis is a combination of two Greek words, 'apo' and 'ptosis,' meaning separation and falling off, respectively. Hippocrates used this word to describe gangrene, which was caused due to bandaging of fractured bones. Apoptosis was distinguished from necrosis in 1970 when John Kerr reported observations of morphological changes occurring during apoptosis. During one experiment, he observed that the disruption of blood supply to the liver tissue resulted in a size reduction of the tissue.
Cellular Injury V: Apoptosis and Autophagy01:22

Cellular Injury V: Apoptosis and Autophagy

Cells respond to damage and stress through highly coordinated processes that decide whether they survive or undergo controlled self-destruction. Two major pathways involved in this regulation are apoptosis, a type of programmed cell death, and autophagy, a survival mechanism that helps cells adapt to adverse conditions.ApoptosisApoptosis removes aged or injured cells to maintain tissue balance. During this process, the cell shrinks, chromatin condenses and fragments, and membrane-bound...
The Intrinsic Apoptotic Pathway01:31

The Intrinsic Apoptotic Pathway

Internal cellular stress, such as cellular injury or hypoxia, triggers intrinsic apoptosis. The B-cell lymphoma 2 (Bcl-2) family of proteins are the primary regulators of the intrinsic apoptotic pathway. For example, during DNA damage, checkpoint proteins, such as Ataxia Telangiectasia Mutated (ATM protein) and Checkpoints Factor-2 (Chk2) proteins, are activated. These proteins phosphorylate p53 which further activates pro-apoptotic proteins, such as Bax, Bak, PUMA, and Noxa, and inhibits...