Rapid isolation of dengue-neutralizing antibodies from single cell-sorted human antigen-specific memory B-cell cultures.
Monitoring antigen-specific memory B cells and the antibodies they encode is important for understanding the specificity, breadth and duration of immune response to an infection or vaccination. The antibodies isolated could further help design vaccine antigens for raising relevant protective immune responses. However, developing assays to measure and isolate antigen-specific memory B cells is technically challenging due to the low frequencies of these cells that exist in the circulating blood. Here, we describe a flow cytometry method to identify and isolate dengue envelope-specific memory B cells using a labeled dengue envelope protein. We enumerated dengue-envelope specific memory B cells from a cohort of dengue seropositive donors using this direct flow cytometry assay. A more established and conventional assay, the cultured B ELISPOT, was used as a benchmark comparator. Furthermore, we were able to confirm the single-sorted memory B-cell specificity by culturing B cells and differentiating them into plasma cells using cell lines expressing CD40L. The culture supernatants were assayed for antigen binding and the ability of the antibodies to neutralize the cognate dengue virus. Moreover, we successfully isolated the heavy and light Ig sequences and expressed them as full-length recombinant antibodies to reproduce the activity seen in culture supernatants. Mapping of these antibodies revealed a novel epitope for dengue 2 virus serotype. In conclusion, we established a reproducible methodology to enumerate antigen-specific memory B cells and assay their encoded antibodies for functional characterization.
a Department of Infectious Diseases and Vaccines-West Point ; PA; Merck Research Laboratories; Merck & Co.; Inc. Kenilworth ; NJ ; USA.
Kara S
KS
Cox
a Department of Infectious Diseases and Vaccines-West Point ; PA; Merck Research Laboratories; Merck & Co.; Inc. Kenilworth ; NJ ; USA.
Aimin
A
Tang
a Department of Infectious Diseases and Vaccines-West Point ; PA; Merck Research Laboratories; Merck & Co.; Inc. Kenilworth ; NJ ; USA.
Zhifeng
Z
Chen
a Department of Infectious Diseases and Vaccines-West Point ; PA; Merck Research Laboratories; Merck & Co.; Inc. Kenilworth ; NJ ; USA.
Melanie S
MS
Horton
a Department of Infectious Diseases and Vaccines-West Point ; PA; Merck Research Laboratories; Merck & Co.; Inc. Kenilworth ; NJ ; USA.
Hao
H
Yan
a Department of Infectious Diseases and Vaccines-West Point ; PA; Merck Research Laboratories; Merck & Co.; Inc. Kenilworth ; NJ ; USA.
Xin-Min
XM
Wang
a Department of Infectious Diseases and Vaccines-West Point ; PA; Merck Research Laboratories; Merck & Co.; Inc. Kenilworth ; NJ ; USA.
Sheri A
SA
Dubey
a Department of Infectious Diseases and Vaccines-West Point ; PA; Merck Research Laboratories; Merck & Co.; Inc. Kenilworth ; NJ ; USA.
Daniel J
DJ
DiStefano
b Integral Molecular Inc. ; Philadelphia ; PA ; USA.
Andrew
A
Ettenger
b Integral Molecular Inc. ; Philadelphia ; PA ; USA.
Rachel H
RH
Fong
b Integral Molecular Inc. ; Philadelphia ; PA ; USA.
Benjamin J
BJ
Doranz
a Department of Infectious Diseases and Vaccines-West Point ; PA; Merck Research Laboratories; Merck & Co.; Inc. Kenilworth ; NJ ; USA.
Danilo R
DR
Casimiro
a Department of Infectious Diseases and Vaccines-West Point ; PA; Merck Research Laboratories; Merck & Co.; Inc. Kenilworth ; NJ ; USA.
Kalpit A
KA
Vora
D057134:Antibodies, Neutralizing / Q000276:immunology*; D000914:Antibodies, Viral / Q000276:immunology*; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D018929:Cell Culture Techniques; D003716:Dengue Virus / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007156:Immunologic Memory; D008297:Male; D014759:Viral Envelope Proteins / Q000276:immunology*
D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D014759:Viral Envelope Proteins
antigen-specific; cell sorting; dengue virus; memory B cell; vaccine