Cell Dynamics in the Germinal Center during an Acute Immune Reaction

An organism which got infected by a pathogen will respond with a very complex immune reaction aimed to destroy the invasor and neutralize its toxicity. Among other things, so called B cells will start producing antibodies which possess a high ability to bind to that individual pathogen. At the same time, the immune system will try to further improve the quality of the produced antibodies. It does that by creating small compartments in the lymphoid tissue, called germinal centers. There, B cells proliferate rapidly while the part of the genome which encodes the antibodies shows a very high mutation rate. After some time, a large number of B cells, each one enconding antibodies with different properties, is available. The cells capable of producing the best fitting antibodies are selected out of that bunch and released into the blood stream. Thus, a few days after the infection, the body is able to produce antibodies with higher affinity towards the given pathogen than the original ones.

Although many details of the germinal center function are well known, the mechanisms governing the dynamics of the B cells and the selection processes within the germinal center are still unclear. The introduction of mathematical models might shed some light into that questions. In this talk, an introduction into the subject will be given and some possible mechanisms and computer simulation results will be presented.