AUTHOR=Neu Savannah D. , Dittel Bonnie N. 

TITLE=Characterization of Definitive Regulatory B Cell Subsets by Cell Surface Phenotype, Function and Context

JOURNAL=Frontiers in Immunology

VOLUME=Volume 12 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.787464

DOI=10.3389/fimmu.2021.787464

ISSN=1664-3224

ABSTRACT=Regulatory B cell or “Breg” is a broad term that represents the anti-inflammatory activity of B cells, but does not describe their individual phenotypes, specific mechanisms of regulation or relevant disease contexts. Thus, given the variety of B cell regulatory mechanisms reported in human disease and their animal models, a more thorough and comprehensive identification strategy is needed for tracking and comparing B cell subsets between research groups and in clinical settings. This review summarizes the discovery process and mechanism of action for well-defined regulatory B cell subsets. These include IL-10 producing plasmablasts/plasma cells and B cell IgD low (BDL) that maintain homeostasis of CD4+Foxp3+ T regulatory cells (Treg). We discuss the importance of conducting thorough B cell phenotyping along with mechanistic studies prior to defining a particular subset of B cells as Breg. Since virtually all B cell subsets can exert regulatory activity, it is