<Li> Lymphoplasmacytoid cell - A cell with a mixture of B lymphocyte and plasma cell morphological features that is thought to be closely related to or a subtype of plasma cells . This cell type is found in pre-malignant and malignant plasma cell dyscrasias that are associated with the secretion of IgM monoclonal proteins; these dyscrasias include IgM monoclonal gammopathy of undetermined significance and Waldenström's macroglobulinemia . </Li> <Li> Memory B cell - Dormant B cell arising from B cell differentiation . Their function is to circulate through the body and initiate a stronger, more rapid antibody response (known as the anamnestic secondary antibody response) if they detect the antigen that had activated their parent B cell (memory B cells and their parent B cells share the same BCR, thus they detect the same antigen). Memory B cells can be generated from T cell - dependent activation through both the extrafollicular response and the germinal center reaction as well as from T cell - independent activation of B1 cells . </Li> <Li> Follicular (FO) B Cell (also known as a B - 2 cell) - Most common type of B cell and, when not circulating through the blood, is found mainly in the lymphoid follicles of secondary lymphoid organs (SLOs). They are responsible for generating the majority of high - affinity antibodies during an infection . </Li> <Li> Marginal zone (MZ) B cell - Found mainly in the marginal zone of the spleen and serves as a first line of defense against blood - borne pathogens, as the marginal zone receives large amounts of blood from the general circulation . They can undergo both T cell - independent and T cell - dependent activation, but preferentially undergo T cell - independent activation . </Li>

Where do b and t cells originate and mature