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Tracking human antigen-specific memory B cells: a sensitive and generalized ELISPOT system.

Shane Crotty·Rachael D Aubert·John Glidewell·Rafi Ahmed
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Abstract

In the interest of better understanding the role of human memory B cells in protection against disease, we developed an assay to quantitate antigen-specific memory B cells in human blood. This assay utilizes a 6-day polyclonal stimulation of PBMC followed by an antigen-specific ELISPOT for the detection of memory B cells that have differentiated into antibody secreting cells (ASC) in vitro. We have used this assay to demonstrate that the anthrax vaccine (AVA; BioThrax) elicits a substantial population of protective-antigen (PA) specific memory B cells, and these B cells satisfy the canonical surface phenotype of human memory B cells: CD19(+)CD20(+)Ig(+)CD27(+). These anti-PA antigen-specific memory B cells are IgG(+) and represent up to 2% of circulating IgG(+) B cells. Furthermore, these results confirm that vaccine-elicited memory B cells reside in the CD27(+) B cell population. This ELISPOT-based system has been designed in a generalized manner, such that the assay can be rapidly adapted to detect human antigen-specific memory B cells of any given specificity. This method should be useful for quantitatively assessing the potency of vaccines and the longevity of B cell immunological memory to various vaccines or infectious diseases.

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Anthrax VaccinesAntibodies, BacterialAntigens, BacterialB-LymphocytesBacterial ToxinsEpitopes, B-LymphocyteFlow CytometryHumansImmunoenzyme TechniquesImmunologic MemoryImmunomagnetic SeparationImmunophenotypingPokeweed MitogensSensitivity and SpecificityStaphylococcus aureusJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Shane Crotty, Rachael D Aubert, John Glidewell, Rafi Ahmed. 2004. Tracking human antigen-specific memory B cells: a sensitive and generalized ELISPOT system.. https://doi.org/10.1016/j.jim.2003.12.015

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