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Quorum-Sensing in CD4(+) T Cell Homeostasis: A Hypothesis and a Model
Afonso R M Almeida1, Inês F Amado, Joseph Reynolds
1Immunobiology Unit, Institute for Molecular Medicine Lisboa, Portugal.
Frontiers in Immunology
|June 2, 2012
Summary
Lymphocyte numbers may be regulated by cells sensing their own population density, similar to bacterial quorum sensing. This mechanism, involving CD4(+) T cells and IL-2, could prevent uncontrolled proliferation and autoimmunity.
Area of Science:
- Immunology
- Cellular Biology
- Systems Biology
Background:
- Lymphocyte homeostasis is traditionally explained by niche competition.
- A new mechanism involving self-population density sensing is proposed.
Purpose of the Study:
- To investigate a quorum-sensing-like mechanism for CD4(+) T cell homeostasis.
- To explore the role of IL-2 in regulating T cell population density.
Main Methods:
- Proposed a quorum-sensing model for CD4(+) T cell regulation.
- Hypothesized IL-2 production by activated CD4(+) T cells and sensing by Treg cells.
- Developed a mathematical model to describe the mechanism.
Main Results:
- CD4(+) T cells may sense their population density via IL-2 signaling.
- This mechanism could regulate activated T cells and prevent over-proliferation.
- Mathematical modeling supports the role of IL-2 and quorum sensing in homeostasis.
Conclusions:
- A novel quorum-sensing-like mechanism may govern CD4(+) T cell homeostasis.
- Dysregulation of this system could contribute to autoimmunity.
- IL-2 plays a critical role in this proposed regulatory pathway.
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