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Cutting Edge: Redox Signaling Hypersensitivity Distinguishes Human Germinal Center B Cells.

ABSTRACT: Differences in the quality of BCR signaling control key steps of B cell maturation and differentiation. Endogenously produced H2O2 is thought to fine tune the level of BCR signaling by reversibly inhibiting phosphatases. However, relatively little is known about how B cells at different stages sense and respond to such redox cues. In this study, we used phospho-specific flow cytometry and high-dimensional mass cytometry (CyTOF) to compare BCR signaling responses in mature human tonsillar B cells undergoing germinal center (GC) reactions. GC B cells, in contrast to mature naive B cells, memory B cells, and plasmablasts, were hypersensitive to a range of H2O2 concentrations and responded by phosphorylating SYK and other membrane-proximal BCR effectors in the absence of BCR engagement. These findings reveal that stage-specific redox responses distinguish human GC B cells.

SUBMITTER: Polikowsky HG

PROVIDER: S-EPMC4530023 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Cutting Edge: Redox Signaling Hypersensitivity Distinguishes Human Germinal Center B Cells.

Polikowsky Hannah G HG Wogsland Cara E CE Diggins Kirsten E KE Huse Kanutte K Irish Jonathan M JM

Journal of immunology (Baltimore, Md. : 1950) 20150708 4

Differences in the quality of BCR signaling control key steps of B cell maturation and differentiation. Endogenously produced H2O2 is thought to fine tune the level of BCR signaling by reversibly inhibiting phosphatases. However, relatively little is known about how B cells at different stages sense and respond to such redox cues. In this study, we used phospho-specific flow cytometry and high-dimensional mass cytometry (CyTOF) to compare BCR signaling responses in mature human tonsillar B cells ...[more]

PMID: 26157177

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