CpG DNA activation and plasma-cell differentiation of CD27− naive human B cells

Abstract

Unmethylated CpG DNA activation of naive CD27 ؊ B cells has been reported to require B-cell-receptor (BCR) cross-linking. We describe a culture system using CpG DNA with sequential steps for T-cell-independent activation of naive CD19 ؉ CD27 ؊ human peripheral blood B cells that induces efficient CD138 ؉ plasma-cell differentiation. CD27 ؉ and CD27 ؊ B cells were cultured in a 3-step system: (1)

PD-1hi Identifies a Novel Regulatory B-cell Population in Human Hepatoma That Promotes Disease Progression

“…This fi nding agrees with that of recent studies showing that activation of TLR by microbial products led to upregulation of PD-1 on monocytes and B cells ( 10,12 ). Notably, the TLR signals, particularly TLR9-CpG ODN interaction, also play an essential role in the terminal differentiation of B cells into plasma cells ( 31 ), but this process requires BCR engagement and costimulation via CD40L ( 32 ). In addition, several recent studies have revealed that T cell-derived IL21 also participates in the terminal differentiation of B cells ( 32 ).…”

Human B Cell Responses to TLR Ligands Are Differentially Modulated by Myeloid and Plasmacytoid Dendritic Cells

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“…However, CD40L can be provided not only by T cells but also by activated B cells. Under such conditions, T cell-independent plasma cell differentiation can take place (61). Recent studies showing that MDCs promote CD40-independent B cell differentiation and isotype switch, mediated by BAFF and a proliferation-inducing ligand (39,40).…”

Arachidonate 5-Lipoxygenase Establishes Adaptive Humoral Immunity by Controlling Primary B Cells and Their Cognate T-Cell Help

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