TitleStochastic model of autocrine and paracrine signals in cell culture assays.
Publication TypeJournal Article
Year of Publication2003
AuthorsBatsilas, L, Berezhkovskii, AM, Shvartsman, SY
JournalBiophys J
Date Published2003 Dec
KeywordsAlgorithms, Animals, Biophysics, Cell Communication, Cell Culture Techniques, Cells, Cultured, Culture Media, Endocytosis, Ligands, Models, Biological, Receptor, Epidermal Growth Factor, Signal Transduction, Stochastic Processes, Temperature

Autocrine signaling systems are commonly studied under cell culture conditions. In a typical cell culture assay, a layer of liquid medium covers a random two-dimensional dispersion of cells, which secrete ligands. In a growing number of experiments, it is important to characterize the spatial range of autocrine and paracrine cell communication. Currently, the spatial distribution of diffusing signals can be analyzed only indirectly, from their effects on the intracellular signaling or physiological responses of autocrine cells. To directly characterize the spatial range of secreted ligands, we propose a stochastic model for autocrine cell cultures and analyze it using a combination of analytical and computational tools. The two main results derived within the framework of this model are 1), an expression for the fraction of autocrine trajectories, i.e., the probability for a ligand to be trapped by the same cell from which it has been secreted; and 2), an expression for the spatial distribution of trapping points of paracrine trajectories. We test these analytical results by stochastic simulations with efficient Brownian dynamics code and apply our model to analyze the spatial operation of autocrine epidermal growth factor receptor systems.

Alternate JournalBiophys. J.