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Updated: Feb 3, 2026
08:08
Isolation and Activation of Murine Lymphocytes
Published on: October 30, 2016
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Does T Cell Activation Require a Quorum of Lymphocytes?
Ghassan A Al-Yassin1, Peter A Bretscher2
1Department of Microbiology and Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada.
Journal of Immunology (Baltimore, Md. : 1950)
|November 7, 2018
Summary
A T cell quorum, not single cell activation, is required for T lymphocyte activation. This finding challenges the Danger Model and explains why self-antigens rarely trigger immune responses.
Area of Science:
- Immunology
- Cellular Biology
Background:
- Current models suggest T lymphocytes can be activated by antigen (Ag) encountering a single T cell under dangerous conditions.
- This framework struggles to explain the infrequent activation of lymphocytes specific for self-antigens.
Purpose of the Study:
- To evaluate the 'quorum sensing' hypothesis for T lymphocyte activation.
- To reconcile existing literature with the proposed T cell quorum requirement.
Main Methods:
- Comprehensive review of historical and contemporary immunology literature.
- Analysis of studies related to T lymphocyte activation by antigen.
Main Results:
- Evidence supports a model where a quorum of T cells, not individual cells, is necessary for T lymphocyte activation.
- This quorum requirement provides a mechanism for the tolerance of self-antigens.
Conclusions:
- The T cell quorum concept offers a more robust explanation for T lymphocyte activation thresholds.
- The Danger Model may be insufficient to explain T cell responses, particularly in the context of self-tolerance.
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