Antigen-specific T-T interactions regulate CD4 T-cell expansion.

@article{Helft2008AntigenspecificTI,
  title={Antigen-specific T-T interactions regulate CD4 T-cell expansion.},
  author={Julie Helft and Alexandra Jacquet and Nathalie T. Joncker and Isabelle Grandjean and Guillaume Doroth{\'e}e and Adrien Kissenpfennig and Bernard Malissen and Polly Matzinger and Olivier Lantz},
  journal={Blood},
  year={2008},
  volume={112 4},
  pages={
          1249-58
        }
}
The regulation of CD4 T-cell numbers during an immune response should take account of the amount of antigen (Ag), the initial frequency of Ag-specific T cells, the mix of naive versus experienced cells, and (ideally) the diversity of the repertoire. Here we describe a novel mechanism of T-cell regulation that potentially deals with all of these parameters. We found that CD4 T cells establish a negative feedback loop by capturing their cognate major histocompatibility class (MHC)/peptide… 

Figures from this paper

Antigen-Stimulated CD4 T Cell Expansion Can Be Limited by Their Grazing of Peptide–MHC Complexes
TLDR
This article interprets the data by a mechanism where CD4+ T cells acquire cognate peptide-MHC (pMHC) complexes from the surface of APCs, thereby increasing the loss rate of pMHC.
Presentation of Acquired Peptide-MHC Class II Ligands by CD4+ Regulatory T Cells or Helper Cells Differentially Regulates Antigen-Specific CD4+ T Cell Response
TLDR
It is shown that acquisition of membrane molecules from APCs is an inherent feature of CD4+ T cell activation and implicate trogocytosis in different subsets of CD 4+ T cells as an intrinsic mechanism for the fine tuning of Ag-specific CD4+.
THE CRITICAL ROLE OF CD4+ TH CELLS IN CD8+ CTL RESPONSES AND ANTI-TUMOR IMMUNITY
TLDR
The goal of this body of research was to elucidate the mechanism by which CD4+ T cells provide help for CD8+ cytotoxic T lymphocyte (CTL) responses in different immunization types, and revealed a novel co-operative role of cognate Th-CTL interactions, contrary to previously known immune-regulatory mechanisms among Th-Th or CTL- CTL interactions.
Cell-to-Cell Interactions and Signals Involved in the Reconstitution of Peripheral CD8+ TCM and TEM Cell Pools
We here describe novel aspects of CD8+ and CD4+ T cell subset interactions that may be clinically relevant and provide new tools for regulating the reconstitution of the peripheral CD8+ T cell pools
CD4+ T cell-released exosomes inhibit CD8+ cytotoxic T-lymphocyte responses and antitumor immunity
TLDR
The data indicate that antigen-specific T-cell EXO may serve as a new type of immunosuppressive reagent for use in transplant rejection and treatment of autoimmune diseases.
Human T Cell Crosstalk Is Induced by Tumor Membrane Transfer
TLDR
Trogocytosis enables cross-reactivity among CD8+ T cells with interchanging roles of effectors and APCs, and may hint at their ability to amplify or restrict reactivity against the tumor and participate in modulation of the anti-cancer immune response.
Modeling the Specific CD4+ T Cell Response against a Tumor Neoantigen
TLDR
It is shown that the presentation of a MHC class II–restricted model Ag (male, DBY) released by dying tumor cells may last more than 4 wk and that the Ag reaches the lymph node and activates naive CD4+ T cells to proliferate and recirculate.
Extrinsic Acquisition of CD80 by Antigen-Specific CD8+ T Cells Regulates Their Recall Immune Responses to Acute Viral Infection
TLDR
CD80 played a role in limiting their expansion and IL-2 production upon exposure to secondary challenge and was observed only in the lymphoid organs but not in the periphery, indicating the trogocytosis of CD80 molecules via interaction between CD8+ T cells and APCs.
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 52 REFERENCES
Antigen persistence is required throughout the expansion phase of a CD4+ T cell response
TLDR
Experiments tracking the proliferation of CD4+ T cells exposed to their cognate antigen in various amounts for different time periods revealed that the division of such cells was contingent on the presence of antigen throughout their expansion phase, even in the presenceof an inflammatory stimulus.
Antigen-independent activation of naive and memory resting T cells by a cytokine combination
TLDR
This novel Ag-independent pathway of T cell activation may play an important role in vivo in recruiting effector T cells at the site of immune response and in maintaining the clonal size of memory T cells in the absence of antigenic stimulation.
Physiological relevance of antigen presentasome (APS), an acquired MHC/costimulatory complex, in the sustained activation of CD4+ T cells in the absence of APCs.
TLDR
The data support the unique concept that naive T cells sustain their activation by removing "antigen presentasome" (APS; eg, antigen-presenting complex) from APCs, thereby releasing the constraint of APC requirement for further activation.
Acquisition of antigen presentasome (APS), an MHC/costimulatory complex, is a checkpoint of memory T-cell homeostasis.
TLDR
It is demonstrated for the first time that acquisition of APS by rested memory T cells is correlated with increased levels of apoptosis in vivo and up-regulation of caspase-3, bcl-x, bak, and bax in the authors' in vitro studies.
Antigen-Experienced CD4 T Cells Display a Reduced Capacity for Clonal Expansion In Vivo That Is Imposed by Factors Present in the Immune Host1
TLDR
It is shown that Ag-experienced CD4 T cells accumulate in lymph nodes more rapidly than naive T cells after in vivo challenge with Ag, whereas the limited capacity for clonal expansion is imposed by some other factor in the immune environment, perhaps residual Ag.
T Cells Compete for Access to Antigen-Bearing Antigen-Presenting Cells
TLDR
Results imply that common properties of T cell responses, such as epitope dominance and secondary response affinity maturation, are the result of competitive interactions between antigen-bearing APC and T cell subsets.
Can B cells turn on virgin T cells?
TLDR
The presenting capacity of B cells in vivo is examined and it is found that resting B cells are indeed unable to activate resting T cells.
In Vivo Detection of Dendritic Cell Antigen Presentation to CD4+ T Cells
TLDR
It is demonstrated that antigen-bearing DC directly interact with naive antigen-specific T cells within the T cell–rich regions of lymph nodes, which results in T cell activation and disappearance in mice that contained the transferred TCR transgenic population.
γ chain required for naïve CD4+ T cell survival but not for antigen proliferation
TLDR
Using monoclonal populations of antigen-specific CD4+ T cells, it is found that naïve T cells cannot survive without γc, whereas memory T cells show no such requirement, calling into question the physiological role of γ c-dependent cytokines as T cell growth factors.
...
1
2
3
4
5
...