Information-Theoretic Analysis of a Model of CAR-4-1BB-Mediated NFκB Activation

Vardges Tserunyan1, Stacey Finley2,3,4

  • 1Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA, USA.

PubMed

Insights

Information theory reveals that fold change in nuclear NFκB concentration better encodes antigen levels than absolute response for CAR T cells. This analysis aids in engineering better cancer therapies.

Area of Science:

  • Systems biology and computational approaches
  • Immunology and cancer therapy
  • Information theory and signal transduction

Background:

  • Chimeric antigen receptor (CAR) T cells are a promising cancer therapy, particularly for hematologic malignancies.
  • Limited success of CAR T cells against solid tumors necessitates deeper understanding of their signaling mechanisms.
  • NFκB signaling pathway plays a crucial role in CAR T cell activation upon antigen recognition.

Purpose of the Study:

  • To apply information theory to a mathematical model of NFκB signaling in CAR T cells.
  • To quantify the information capacity and fidelity of CAR-mediated NFκB signal transduction.
  • To explore strategies for enhancing CAR T cell efficacy through improved signaling.

Main Methods:

  • Mathematical modeling of NFκB signaling initiated by CAR engagement with antigen.
  • Estimation of channel capacity for CAR-4-1BB-mediated NFκB signal transduction.
  • Evaluation of pathway's ability to distinguish antigen concentrations and assessment of signaling fidelity.

Main Results:

  • Fold change in nuclear NFκB concentration demonstrated higher channel capacity than absolute NFκB response.
  • Signal transduction errors predominantly led to underestimation of encountered antigen concentration.
  • Disabling IKKβ deactivation enhanced signaling fidelity, especially against targets with antigen-negative cells.

Conclusions:

  • Information-theoretic analysis provides novel insights into biological signal transduction mechanisms.
  • Understanding signal encoding and fidelity can guide the rational engineering of CAR T cells for improved cancer therapy.
  • The study highlights the importance of relative signal changes over absolute levels for effective T cell activation.

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