Human memory B cells play a vital role in the long-term : Background protection of the host from pathogenic re-challenge. In recent years the importance of a number of different memory B cell subsets that can be formed in response to vaccination or infection has started to become clear. To study memory B cell responses, cells can be cultured allowing for an ex vivo, increase in cell number an...

Background: Human memory B cells play a vital role in the long-term protection of the host from pathogenic re-challenge. In recent years the importance of a number of different memory B cell subsets that can be formed in response to vaccination or infection has started to become clear. To study memory B cell responses, cells can be cultured ex vivo, allowing for an increase in cell number and a...

Dynamic interactions between CD4(+) T cells and B cells are needed for humoral immunity and CD4(+) T cell memory. It is not known whether B cells are needed early on to induce the formation of memory precursor cells or are needed later to sustain memory cells. In this study, primary and memory CD4(+) T cells responses were followed in wild-type mice that were depleted of mature B cells by anti-...

The impact of memory B cells and alloantibodies on the ability to induce transplantation tolerance has not been elucidated. We have developed a murine heart transplant model that isolates the contributions of functional memory B cells from memory T cells in allograft rejection. Memory 3-83 B cells with dual specificity for H-2K(k) and H-2K(b) were generated in 3-83 Igi BCR knockin (BALB/c backg...

Human immunodeficiency virus (HIV) disease leads to impaired B cell and antibody responses through mechanisms that remain poorly defined. A unique memory B cell subpopulation (CD20(hi)/CD27(lo)/CD21(lo)) in human tonsillar tissues was recently defined by the expression of the inhibitory receptor Fc-receptor-like-4 (FCRL4). In this study, we describe a similar B cell subpopulation in the blood o...

Humoral immunity is maintained by long-lived plasma cells, constitutively secreting antibodies, and nonsecreting resting memory B cells that are rapidly reactivated upon antigen encounter. The activation requirements for resting memory B cells, particularly the role of T helper cells, are unclear. To analyze the activation of memory B cells, mice were immunized with human cytomegalovirus, a com...

Memory B cells play essential roles in the maintenance of long-term immunity and may be important in the pathogenesis of autoimmune disease, but how these cells are distinguished from their naive precursors is poorly understood. To address this, it would be important to understand how gene expression differs between memory and naive B cells to elucidate memory-specific functions. Using model sy...

The mechanisms that regulate B cell memory and the rapid recall response to antigen remain poorly defined. This study focuses on the rapid expression of B cell memory upon antigen recall in vivo, and the replenishment of quiescent B cell memory that follows. Based on expression of CD138 and B220, we reveal a unique and major subtype of antigen-specific memory B cells (B220 2 CD138 2 ) that are ...

Asplenic patients have a lifelong risk of overwhelming post-splenectomy infection and have been reported to have low numbers of peripheral blood IgM memory B cells. The clinical value of quantitation of memory B cells as an indicator of splenic abnormality or risk of infection has been unclear. To assess changes in B cell sub-populations after splenectomy we studied patients recruited to a sple...

Memory B cells can be produced from the classical germinal center (GC) pathway or a less understood GC-independent route. We used antigen-based cell enrichment to assess the relative contributions of these pathways to the polyclonal memory B cell pool. We identified a CD38(+) GL7(+) B cell precursor population that differentiated directly into IgM(+) or isotype-switched (sw) Ig(+) memory B cell...