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Fluorescently labeled dengue viruses as probes to identify antigen-specific memory B cells by multiparametric flow cytometry.

ABSTRACT: Low frequencies of memory B cells in the peripheral blood make it challenging to measure the functional and phenotypic characteristics of this antigen experienced subset of B cells without in vitro culture. To date, reagents are lacking to measure ex vivo frequencies of dengue virus (DENV)-specific memory B cells. We wanted to explore the possibility of using fluorescently labeled DENV as probes to detect antigen-specific memory B cells in the peripheral blood of DENV immune individuals. Alexa Fluor dye-labeled DENV yielded viable virus that could be stored at -80°C for long periods of time. Using a careful gating strategy and methods to decrease non-specific binding, we were able to identify a small frequency of B cells from dengue immune individuals that bound labeled DENV. Sorted DENV(+) B cells from immune, but not naïve donors secreted antibodies that bound DENV after in vitro stimulation. Overall, Alexa Fluor dye-labeled DENVs are useful reagents to enable the detection and characterization of memory B cells in DENV immune individuals.

SUBMITTER: Woda M

PROVIDER: S-EPMC4440233 | biostudies-other | 2015 Jan

REPOSITORIES: biostudies-other

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Fluorescently labeled dengue viruses as probes to identify antigen-specific memory B cells by multiparametric flow cytometry.

Woda Marcia M Mathew Anuja A

Journal of immunological methods 20141210

Low frequencies of memory B cells in the peripheral blood make it challenging to measure the functional and phenotypic characteristics of this antigen experienced subset of B cells without in vitro culture. To date, reagents are lacking to measure ex vivo frequencies of dengue virus (DENV)-specific memory B cells. We wanted to explore the possibility of using fluorescently labeled DENV as probes to detect antigen-specific memory B cells in the peripheral blood of DENV immune individuals. Alexa F ...[more]

PMID: 25497702

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Dataset Information

Fluorescently labeled dengue viruses as probes to identify antigen-specific memory B cells by multiparametric flow cytometry.

Publications

Fluorescently labeled dengue viruses as probes to identify antigen-specific memory B cells by multiparametric flow cytometry.

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