Our ability to produce high affinity antibodies is critical for our survival against numerous infections, but this system is also causing many tumors.To optimize the initial wave of antibody defense against infections, the B-lymphocytes with highest antigen affinity of their B cell receptor (BCR) are selected to generate the extrafollicular plasmablast responses.B-cells with less strong antigen binding are selected for the germinal center where they undergo somatic hypermutation (SH) of their antibody genes.