Intrinsic Noise in the Specific Response of the Immune System

by Robert Mulet (Dept. of Theoretical Physics, Univ. de La Habana)

Tuesday 6 Jul 2010, 16:00 → 17:00 Europe/Rome

Aula Rasetti (Dipartimento di Fisica - Ed- G. Marconi)

We develop a stochastic model to capture the specific response of the immune system. The model, solved first, in the mean field approximation shows a rich phase diagram that reproduces the standard scenarios of the immune response. Then, within the Effective Stability Approximation we correct the properties of this phase diagram taking into account the role of the intrinsic fluctuations. We show that these fluctuations may, indeed, change the structure of the phase diagram, and in particular, may completely destroy the predicted limit cycles. Then, considering a Linear Noise Appr! oximation we show that, also because of the intrinsic fluctuations, the dynamic of the system is dominated by characteristic frequencies. All the predictions were tested with Monte Carlo (Gillespie's algorithm) simulations.