Optimal evolutionary decision-making to store immune memory
Abstract
The adaptive immune system provides a diverse set of molecules that can mount specific responses against a multitude of pathogens. Memory is a key feature of adaptive immunity, which allows organisms to respond more readily upon re-infections. However, differentiation of memory cells is still one of the least understood cell fate decisions. Here, we introduce a mathematical framework to characterize optimal strategies to store memory to maximize the utility of immune response over an organism's lifetime. We show that memory production should be actively regulated to balance between affinity and cross-reactivity of immune receptors for an effective protection against evolving pathogens. Moreover, we predict that specificity of memory should depend on the organism's lifespan, and shorter-lived organisms with fewer pathogenic encounters should store more cross-reactive memory. Our framework provides a baseline to gauge the efficacy of immune memory in light of an organism's coevolutionary history with pathogens.
Data availability
Numerical data generated for all figures and the corresponding code will be provided for publication.
Article and author information
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Funding
Deutsche Forschungsgemeinschaft (SFB1310)
- Armita Nourmohammad
Max Planck Society (MPRG funding)
- Armita Nourmohammad
University of Washington (Royalty Research Fund: A153352)
- Armita Nourmohammad
Max Planck Institute for Dynamics and Self-organization (Open-access funding)
- Armita Nourmohammad
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Schnaack & Nourmohammad
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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