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arXiv · 1605.01290

The role of idiotypic interactions in the adaptive immune system: a belief-propagation approach

Abstract

In this work we use belief-propagation techniques to study the equilibrium behaviour of a minimal model for the immune system comprising interacting T and B clones. We investigate the effect of the so-called idiotypic interactions among complementary B clones on the system's activation. Our result shows that B-B interactions increase the system's resilience to noise, making clonal activation more stable, while increasing the cross-talk between different clones. We derive analytically the noise level at which a B clone gets activated, in the absence of cross-talk, and find that this increases with the strength of idiotypic interactions and with the number of T cells signalling the B clone. We also derive, analytically and numerically, via population dynamics, the critical line where clonal cross-talk arises. Our approach allows us to derive the B clone size distribution, which can be experimentally measured and gives important information about the adaptive immune system response to antigens and vaccination.

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Silvia Bartolucci, Alexander Mozeika, Alessia Annibale. 2016-05-04. The role of idiotypic interactions in the adaptive immune system: a belief-propagation approach. https://doi.org/10.1088/1742-5468%2F2016%2F08%2F083402

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