The role of lipid rafts in cell surface BCR antigen binding dynamics

B Lymphocyte activation results from the stimulation by large immune complexes involving antigens, antibodies, rafts and complement factors. Cell activation requires co-localization of the interacting molecular components. One of the main elements leading to this localization is the presence on the cell surface of lipid rafts. We show here that an appropriate amount of lipid rafts help to significantly (2- 3 orders of magnitude) raise the sensitivity of B lymphocyte to surrounding high valence antigens. The analysis was done using a newly developed graphically visualized, Monte Carlo (MC) simulation of the cell surface dynamics. Currently this platform represents a feasible, advanced and reliable framework to investigate the cell surface in general. We describe the model and determine, utilizing our model, the effect of lipid rafts surface fraction on the properties of B cell response to immune complexes. We validate our results using an approximate set of ODEs.