Maximum entropy and population heterogeneity in continuous cell cultures

Abstract

Continuous cultures of mammalian cells are complex systems displaying hallmark phenomena of nonlinear dynamics, such as multi-stability, hysteresis, as well as sharp transitions between different metabolic states. In this context mathematical models may suggest control strategies to steer the system towards desired states. Although even clonal populations are known to exhibit cell-to-cell variability, most of the currently studied models assume that the population is homogeneous. To overcome this limitation, we use the maximum entropy principle to model the phenotypic distribution of cells in a chemostat as a function of the dilution rate. We consider the coupling between cell metabolism and extracellular variables describing the state of the bioreactor and take into account the impact of toxic byproduct accumulation on cell viability. We present a formal solution for the stationary state of the chemostat and show how to apply it in two examples. First, a simplified model of cell metabolism where the exact solution is tractable, and then a genome-scale metabolic network of the Chinese hamster ovary (CHO) cell line. Along the way we discuss several consequences of heterogeneity, such as: qualitative changes in the dynamical landscape of the system, increasing concentrations of byproducts that vanish in the homogeneous case, and larger population sizes.

References in corpus (13)

• Weak pairwise correlations imply strongly correlated network states in a neural population
• Expectation Propagation for approximate Bayesian inference
• The protein cost of metabolic fluxes: prediction from enzymatic rate laws and cost minimization
• Creation and analysis of biochemical constraint-based models: the COBRA Toolbox v3.0
• Statistical mechanics for metabolic networks during steady-state growth
• Growth against entropy in bacterial metabolism: the phenotypic trade-off behind empirical growth rate distributions in E. coli
• An analytic approximation of the feasible space of metabolic networks
• Characterizing steady states of genome-scale metabolic networks in continuous cell cultures
• An analytically tractable model for community ecology with many species
• Quantifying the entropic cost of cellular growth control
• Cell population heterogeneity driven by stochastic partition and growth optimality
• Fast inference of ill-posed problems within a convex space
• Microenvironmental cooperation promotes early spread and bistability of a Warburg-like phenotype

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• Evolutionary emergent metabolic interactions in cell cultures: A Statistical Mechanics point of view
• Cooperative metabolic resource allocation in spatially-structured systems