Spatiotemporal dynamics of immunogenic tumors

A mathematical model, consisting of a system of two coupled reaction-diffusion partial differential equations describing the interaction between solid tumor and immune system (termed as effector cells), is proposed here. The main focus is on the analysis of the spatiotemporal dynamics of tumor cells and immune cells. The resulting system is analyzed and numerical simulations are presented. Different types of spatial patterns with respect to different initial conditions, and time are observed. Their analysis and mechanism of spatiotemporal pattern formation in immunogenic tumor are studied. Spatiotemporal perturbation around non-spatial steady state beyond the linear regime is obtained based on the analysis of higher-order perturbation terms.

Spatiotemporal pattern formation in E. coli biofilms explained by a simple physical energy balance

We demonstrate that a minimal physical model based on phase separation describes well the spontaneous formation of regular spatial patterns during the growth of an Escherichia coli biofilm.

Controlling spatiotemporal pattern formation in a concentration gradient with a synthetic toggle switch

The formation of spatiotemporal patterns of gene expression is frequently guided by gradients of diffusible signaling molecules. The toggle switch subnetwork, composed of two cross-repressing transcription factors, is a common component of gene regulatory networks in charge of patterning, converting the continuous information provided by the gradient into discrete abutting stripes of gene expression. We present a synthetic biology framework to understand and characterize the spatiotemporal patterning properties of the toggle switch. To this end, we built a synthetic toggle switch controllable by diffusible molecules in Escherichia coli. We analyzed the patterning capabilities of the circuit by combining quantitative measurements with a mathematical reconstruction of the underlying dynamical system. The toggle switch can produce robust patterns with sharp boundaries, governed by bistability and hysteresis. We further demonstrate how the hysteresis, position, timing, and precision of the boundary can be controlled, highlighting the dynamical flexibility of the circuit.