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Updated: Aug 8, 2026
Adenoviral Transduction of Naive CD4 T Cells to Study Treg Differentiation
Published on: August 13, 2013
Effector CD4 cell tolerization is mediated through functional inactivation and involves preferential impairment of
Meixiao Long1, Amy D Higgins, Marianne A Mihalyo
1Center for Immunotherapy of Cancer and Infectious Diseases, University of Connecticut Health Center, Farmington, CT 06030, USA.
Insights
Self-antigen exposure functionally inactivates CD4 effector T cells within 24 hours, primarily impairing cytokine production like TNF-alpha. This tolerization process affects both IFN-gamma-producing and non-producing cells, demonstrating functional inactivation rather than selective cell deletion.
Area of Science:
- Immunology
- T cell biology
- Peripheral tolerance
Background:
- Effector/memory T cells can undergo peripheral tolerization upon encountering self-antigens.
- Understanding the mechanisms of T cell tolerance is crucial for autoimmune disease research.
Purpose of the Study:
- To investigate the kinetics and mechanisms of CD4 effector T cell tolerization by self-antigen.
- To differentiate between functional inactivation and selective deletion of effector T cells.
Main Methods:
- Exposure of CD4 effector T cells to self-antigen (self-HA).
- Analysis of cytokine production (TNF-alpha, IFN-gamma, IL-2) and proliferation.
- Fractionation of T cells based on IFN-gamma expression for secondary stimulation assays.
Main Results:
- Self-antigen rapidly impairs TNF-alpha production (within 24h) and IFN-gamma production in CD4 effectors.
- Prolonged self-antigen exposure is needed to affect IL-2 expression and proliferation.
- Both IFN-gamma-producing and non-producing effector CD4 cells are functionally inactivated, with minimal deletion observed.
Conclusions:
- Peripheral tolerization of CD4 effector T cells by self-antigen is primarily mediated by functional inactivation of effector-competent cells.
- This functional inactivation affects cytokine production capacity rather than leading to selective cell death.
Abstract:
It has recently been shown that effector/memory T cells can undergo peripheral tolerization in response to self-antigen. In the present study, we found that within 24h self-antigen profoundly impairs the ability of CD4 effectors to express TNF-alpha (and to a lesser extent IFN-gamma); however, several days of self-antigen exposure is required to impair non-effector functions such as IL-2 expression and proliferation. Since only half of the initial effector CD4 cell population expresses effector cytokines following brief antigenic stimulation, tolerization might have been mediated either through functional inactivation of effector-competent cells, or alternatively by the selective deletion of competent and expansion of non-competent cells. When briefly stimulated effectors were fractionated based on their expression of IFN-gamma, the IFN-gamma(-) sub-population was able to express IFN-gamma following secondary stimulation, indicating that all effector CD4 cells are functionally competent. Furthermore, both IFN-gamma(+) and IFN-gamma(-) sub-populations underwent tolerization in response to self-HA (although the former was slightly more prone to deletion at later time points). Thus, effector CD4 cell tolerization is mediated primarily through the functional inactivation of effector-competent cells.
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