Polysaccharide-Specific Memory B Cells Predict Protection against Experimental Human Pneumococcal Carriage


Pennington, SH, Pojar, S, Mitsi, E, Gritzfeld, JF, Nikolaou, E, Solorzano, C, Owugha, JT, Masood, Q, Gordon, MA ORCID: 0000-0002-0629-0884, Wright, AD et al (show 4 more authors) (2016) Polysaccharide-Specific Memory B Cells Predict Protection against Experimental Human Pneumococcal Carriage. AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE, 194 (12). pp. 1523-1531.

[img] Text
Polysaccharide-specific Memory B-cells Predict Protection Against Experimental Human Pneumococcal Carriage - Clean.pdf - Author Accepted Manuscript
Download (1MB)

Abstract

<h4>Rationale</h4>We have previously demonstrated that experimental pneumococcal carriage enhances immunity and protects healthy adults against carriage reacquisition after rechallenge with a homologous strain.<h4>Objectives</h4>To investigate the role of naturally acquired pneumococcal protein and polysaccharide (PS)-specific immunity in protection against carriage acquisition using a heterologous challenge model.<h4>Methods</h4>We identified healthy volunteers that were naturally colonized with pneumococcus and, after clearance of their natural carriage episode, challenged them with a heterologous 6B strain. In another cohort of volunteers we assessed 6BPS-specific, PspA-specific, and PspC-specific IgG and IgA plasma and memory B-cell populations before and 7, 14, and 35 days after experimental pneumococcal inoculation.<h4>Measurements and main results</h4>Heterologous challenge with 6B resulted in 50% carriage among volunteers with previous natural pneumococcal carriage. Protection from carriage was associated with a high number of circulating 6BPS IgG-secreting memory B cells at baseline. There were no associations between protection from carriage and baseline levels of 6BPS IgG in serum or nasal wash, PspA-specific, or PspC-specific memory B cells or plasma cells. In volunteers who did not develop carriage, the number of circulating 6BPS memory B cells decreased and the number of 6BPS plasma cells increased postinoculation.<h4>Conclusions</h4>Our data indicate that naturally acquired PS-specific memory B cells, but not levels of circulating IgG at time of pneumococcal exposure, are associated with protection against carriage acquisition.

Item Type: Article
Uncontrolled Keywords: pneumococcal carriage, pneumococcal polysaccharide, memory B cells, plasma B cells, antibodies
Depositing User: Symplectic Admin
Date Deposited: 22 May 2017 12:42
Last Modified: 19 Jan 2023 07:04
DOI: 10.1164/rccm.201512-2467OC
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3007600
Dimensions
Altmetric
CORE (COnnecting REpositories)