Ag-dependent (in silico) approach implies a deterministic kinetics for homeostatic memory cell turnover

TL;DR

This paper uses an in silico antigen-dependent model to simulate immune memory cell turnover, suggesting a deterministic process that contrasts with previous stochastic assumptions based on empirical data.

Contribution

It introduces an antigen-dependent computational approach to model immune memory dynamics, challenging prior stochastic interpretations.

Findings

Deterministic kinetics for homeostatic memory cell turnover

Contradicts previous stochastic models by Choo et al.

Highlights need for more empirical studies on immune homeostasis

Abstract

Verhulst-like mathematical modeling has been used to investigate several complex biological issues, such as immune memory equilibrium and cell-mediated immunity in mammals. The regulation mechanisms of both these processes are still not sufficiently understood. In a recent paper, Choo et al. [J. Immunol., v. 185, pp. 3436-44, 2010], used an Ag-independent approach to quantitatively analyze memory cell turnover from some empirical data, and concluded that immune homeostasis behaves stochastically, rather than deterministically. In the paper here presented, we use an in silico Ag-dependent approach to simulate the process of antigenic mutation and study its implications for memory dynamics. Our results have suggested a deterministic kinetics for homeostatic equilibrium, what contradicts the Choo et al. findings. Accordingly, our calculations are an indication that a more extensive empirical protocol for studying the homeostatic turnover should be considered.