A Three‐Dimensional Model of Intercellular Calcium Signaling in Epithelial Cells

We have developed a fully three‐dimensional (3D) model of calcium signaling in epithelial cells based on a set of reaction diffusion equations that are solved on a large‐scale finite‐element code in three dimensions. We have explicitly included the cellular compartments including the cell nucleus, cytoplasm, and gap junctions. The model allows for buffering of free Ca2+, calcium‐induced calcium release, and the explicit inclusion of mobile buffers. To make quantitative comparisons to experimental results, we used fluorescence microscopy images of cells to generate an accurate mesh describing cell morphology. We found that Ca2+ wave propagation through the tissue is a function of both initial conditions used to start the wave and various geometrical parameters that affect propagation such as gap junction density and distribution, and the presence of nuclei. The exogenous dyes used in experimental imaging also affect wave propagation.

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