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

Published on: January 22, 2019

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Small molecule inhibition of Csk alters affinity recognition by T cells

Boryana N Manz1, Ying Xim Tan1, Adam H Courtney1

  • 1Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Division of Rheumatology, Department of Medicine, University of California, San Francisco, San Francisco, United States.

Elife
|August 25, 2015
PubMed

Insights

Inhibiting C-terminal Src kinase (Csk) enhances T cell receptor (TCR) signaling and proliferation. This finding reveals Csk’s critical role in setting the TCR signaling threshold and improving T cell responses to weak agonists.

Area of Science:

  • Immunology
  • Cell Signaling
  • Molecular Biology

Background:

  • C-terminal Src kinase (Csk) is a key negative regulator of Src-family kinases (SFK).
  • Csk controls basal and inducible receptor signaling pathways.
  • Understanding Csk's role in T cell antigen receptor (TCR) signaling is crucial for immunology.

Purpose of the Study:

  • To investigate the regulatory role of Csk activity in TCR signaling.
  • To determine how Csk inhibition impacts T cell activation and proliferation.
  • To elucidate Csk's function in TCR signaling threshold and affinity recognition.

Main Methods:

  • Utilized a mouse model with mutated Csk (Csk(AS)) for rapid, specific inhibition by a small molecule.
  • Administered small molecule inhibitor during TCR stimulation.
  • Analyzed TCR signaling strength, duration, T cell proliferation, and response to weak agonists.

Main Results:

  • Inhibition of Csk(AS) resulted in stronger and more prolonged TCR signaling.
  • Csk inhibition led to increased T cell proliferation.
  • Enhanced T cell activation by weak agonists was observed upon Csk inhibition.
  • A small increase in SFK activity was sufficient to potentiate T cell responses to weak agonists.

Conclusions:

  • Csk plays a significant role in regulating basal TCR signaling.
  • Csk is critical for setting the TCR signaling threshold.
  • Csk influences T cell affinity recognition and response to weak agonists.
Keywords:
Src kinasescell biologyimmunologylymphocytemousereceptorssignal transductiontyrosine phosphorylation

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