Understanding memory B cell selection.
The mammalian adaptive immune system has evolved over millions of years to become an incredibly effective defense against foreign antigens. The adaptive immune system's humoral response creates plasma B cells and memory B cells, each with their own immunological objectives. The affinity maturation process is widely viewed as a heuristic to solve the global optimization problem of finding B cells with high affinity to the antigen. However, memory B cells appear to be purposely selected earlier in the affinity maturation process and have lower affinity. We propose that this memory B cell selection process may be an approximate solution to two optimization problems: optimizing for affinity to similar antigens in the future despite mutations or other minor differences, and optimizing to warm start the generation of plasma B cells in the future. We use simulations to provide evidence for our hypotheses, taking into account data showing that certain B cell mutations are more likely than others. Our findings are consistent with memory B cells having high-affinity to mutated antigens, but do not provide strong evidence that memory B cells will be more useful than selected naive B cells for seeding the secondary germinal centers.
['Lindsly|Stephen|S|', 'Gupta|Maya|M|', 'Stansbury|Cooper|C|', 'Rajapakse|Indika|I|']
D056704:Adaptive Immunity D000818:Animals D000941:Antigens D001402:B-Lymphocytes D018858:Germinal Center D007156:Immunologic Memory
Memory B cell Plasma B cell Warm start Germinal center Adversarial mutation