Predicting cell adhesion probability via the biochemical stochastic pi-calculus

This paper presents a stochastic model of the lymphocytes recruitment in inflamed brain microvessels. The framework used is based on stochastic process algebras for mobile systems. The automatic tool used in the simulation is the biochemical stochastic $\pi$-calculus. The biochemical stochastic $\pi$-calculus is an efficient tool for describing the concurrency of the different interactions driving the phases of lymphocytes recruitment. It models a biochemical systems as a set of concurrent processes selected according to a suitable probability distribution in order to quantitatively describe the rates and the times at which the reactions occur. We use here this tool to model and simulate the molecular mechanisms involved in encephalitogenic lymphocytes recruitment. In particular, we show that the model predicts the adhesion probability of the lymphocytes as a function of contact time of the cells with endothelium. The results of the model reproduce, within the experimental errors, the behavior of the data obtained either from laboratory measurements or from a classical deterministic treatment of the mechanics of cell adhesion.