Cargando…

A Nonfunctional Opsonic Antibody Response Frequently Occurs after Pneumococcal Pneumonia and Is Associated with Invasive Disease

Naturally acquired opsonic antipneumococcal antibodies are commonly found in nonvaccinated adults and confer protection against infection and colonization. Despite this, only limited data exist regarding the adaptive immune response after pneumococcal exposure. To investigate the dynamics of natural...

Descripción completa

Detalles Bibliográficos
Autores principales: Uddén, Fabian, Ahl, Jonas, Littorin, Nils, Strålin, Kristoffer, Athlin, Simon, Riesbeck, Kristian
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Society for Microbiology 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7002313/
https://www.ncbi.nlm.nih.gov/pubmed/32024704
http://dx.doi.org/10.1128/mSphere.00925-19
_version_ 1783494351389720576
author Uddén, Fabian
Ahl, Jonas
Littorin, Nils
Strålin, Kristoffer
Athlin, Simon
Riesbeck, Kristian
author_facet Uddén, Fabian
Ahl, Jonas
Littorin, Nils
Strålin, Kristoffer
Athlin, Simon
Riesbeck, Kristian
author_sort Uddén, Fabian
collection PubMed
description Naturally acquired opsonic antipneumococcal antibodies are commonly found in nonvaccinated adults and confer protection against infection and colonization. Despite this, only limited data exist regarding the adaptive immune response after pneumococcal exposure. To investigate the dynamics of naturally acquired antipneumococcal immunity in relation to an episode of infection, opsonic antibody activity was studied with paired acute-phase and convalescent-phase sera obtained from 54 patients with pneumococcal community-acquired pneumonia (CAP) using an opsonophagocytic assay (OPA). Results were compared with clinical characteristics and anticapsular immunoglobulin (Ig) concentrations. Interestingly, a nonfunctional opsonic antibody response (characterized by a decreased convalescent-phase serum OPA titer compared to that of the acute-phase serum or undetectable titers in both sera) was observed in 19 (35%) patients. A nonfunctional convalescent-phase response was significantly more common among patients with invasive pneumococcal disease (i.e., bacteremia) than in patients without invasive disease (53%; P = 0.019). Remaining individuals exhibited either an increased convalescent-phase OPA titer (n = 24 [44%]) or a detectable, but unchanged, titer at both time points (n = 11 [20%]). No correlation was found between anticapsular Ig concentrations and OPA titers. Our findings indicate that an episode of pneumococcal infection may act as an immunizing event, leading to an improved antipneumococcal adaptive immune status. However, in some cases, when patients with CAP also suffer from bacteremia, a nonfunctional opsonic antibody response may occur. Furthermore, the results suggest that factors other than anticapsular Ig concentrations are important for opsonic antibody activity in serum. IMPORTANCE Numerous reports on the dynamics of antipneumococcal immunity in relation to immunization with pneumococcal vaccines and on the prevalence of naturally acquired immunity in various populations have been published. In contrast, studies on the dynamics of the humoral immune response triggered by pneumococcal infection are scarce. This study provides valuable information that will contribute to fill this knowledge gap. Our main results indicate that a functional immune response frequently fails to occur after CAP, predominantly among patients with simultaneous bacteremia.
format Online
Article
Text
id pubmed-7002313
institution National Center for Biotechnology Information
language English
publishDate 2020
publisher American Society for Microbiology
record_format MEDLINE/PubMed
spelling pubmed-70023132020-02-11 A Nonfunctional Opsonic Antibody Response Frequently Occurs after Pneumococcal Pneumonia and Is Associated with Invasive Disease Uddén, Fabian Ahl, Jonas Littorin, Nils Strålin, Kristoffer Athlin, Simon Riesbeck, Kristian mSphere Research Article Naturally acquired opsonic antipneumococcal antibodies are commonly found in nonvaccinated adults and confer protection against infection and colonization. Despite this, only limited data exist regarding the adaptive immune response after pneumococcal exposure. To investigate the dynamics of naturally acquired antipneumococcal immunity in relation to an episode of infection, opsonic antibody activity was studied with paired acute-phase and convalescent-phase sera obtained from 54 patients with pneumococcal community-acquired pneumonia (CAP) using an opsonophagocytic assay (OPA). Results were compared with clinical characteristics and anticapsular immunoglobulin (Ig) concentrations. Interestingly, a nonfunctional opsonic antibody response (characterized by a decreased convalescent-phase serum OPA titer compared to that of the acute-phase serum or undetectable titers in both sera) was observed in 19 (35%) patients. A nonfunctional convalescent-phase response was significantly more common among patients with invasive pneumococcal disease (i.e., bacteremia) than in patients without invasive disease (53%; P = 0.019). Remaining individuals exhibited either an increased convalescent-phase OPA titer (n = 24 [44%]) or a detectable, but unchanged, titer at both time points (n = 11 [20%]). No correlation was found between anticapsular Ig concentrations and OPA titers. Our findings indicate that an episode of pneumococcal infection may act as an immunizing event, leading to an improved antipneumococcal adaptive immune status. However, in some cases, when patients with CAP also suffer from bacteremia, a nonfunctional opsonic antibody response may occur. Furthermore, the results suggest that factors other than anticapsular Ig concentrations are important for opsonic antibody activity in serum. IMPORTANCE Numerous reports on the dynamics of antipneumococcal immunity in relation to immunization with pneumococcal vaccines and on the prevalence of naturally acquired immunity in various populations have been published. In contrast, studies on the dynamics of the humoral immune response triggered by pneumococcal infection are scarce. This study provides valuable information that will contribute to fill this knowledge gap. Our main results indicate that a functional immune response frequently fails to occur after CAP, predominantly among patients with simultaneous bacteremia. American Society for Microbiology 2020-02-05 /pmc/articles/PMC7002313/ /pubmed/32024704 http://dx.doi.org/10.1128/mSphere.00925-19 Text en Copyright © 2020 Uddén et al. https://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license (https://creativecommons.org/licenses/by/4.0/) .
spellingShingle Research Article
Uddén, Fabian
Ahl, Jonas
Littorin, Nils
Strålin, Kristoffer
Athlin, Simon
Riesbeck, Kristian
A Nonfunctional Opsonic Antibody Response Frequently Occurs after Pneumococcal Pneumonia and Is Associated with Invasive Disease
title A Nonfunctional Opsonic Antibody Response Frequently Occurs after Pneumococcal Pneumonia and Is Associated with Invasive Disease
title_full A Nonfunctional Opsonic Antibody Response Frequently Occurs after Pneumococcal Pneumonia and Is Associated with Invasive Disease
title_fullStr A Nonfunctional Opsonic Antibody Response Frequently Occurs after Pneumococcal Pneumonia and Is Associated with Invasive Disease
title_full_unstemmed A Nonfunctional Opsonic Antibody Response Frequently Occurs after Pneumococcal Pneumonia and Is Associated with Invasive Disease
title_short A Nonfunctional Opsonic Antibody Response Frequently Occurs after Pneumococcal Pneumonia and Is Associated with Invasive Disease
title_sort nonfunctional opsonic antibody response frequently occurs after pneumococcal pneumonia and is associated with invasive disease
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7002313/
https://www.ncbi.nlm.nih.gov/pubmed/32024704
http://dx.doi.org/10.1128/mSphere.00925-19
work_keys_str_mv AT uddenfabian anonfunctionalopsonicantibodyresponsefrequentlyoccursafterpneumococcalpneumoniaandisassociatedwithinvasivedisease
AT ahljonas anonfunctionalopsonicantibodyresponsefrequentlyoccursafterpneumococcalpneumoniaandisassociatedwithinvasivedisease
AT littorinnils anonfunctionalopsonicantibodyresponsefrequentlyoccursafterpneumococcalpneumoniaandisassociatedwithinvasivedisease
AT stralinkristoffer anonfunctionalopsonicantibodyresponsefrequentlyoccursafterpneumococcalpneumoniaandisassociatedwithinvasivedisease
AT athlinsimon anonfunctionalopsonicantibodyresponsefrequentlyoccursafterpneumococcalpneumoniaandisassociatedwithinvasivedisease
AT riesbeckkristian anonfunctionalopsonicantibodyresponsefrequentlyoccursafterpneumococcalpneumoniaandisassociatedwithinvasivedisease
AT uddenfabian nonfunctionalopsonicantibodyresponsefrequentlyoccursafterpneumococcalpneumoniaandisassociatedwithinvasivedisease
AT ahljonas nonfunctionalopsonicantibodyresponsefrequentlyoccursafterpneumococcalpneumoniaandisassociatedwithinvasivedisease
AT littorinnils nonfunctionalopsonicantibodyresponsefrequentlyoccursafterpneumococcalpneumoniaandisassociatedwithinvasivedisease
AT stralinkristoffer nonfunctionalopsonicantibodyresponsefrequentlyoccursafterpneumococcalpneumoniaandisassociatedwithinvasivedisease
AT athlinsimon nonfunctionalopsonicantibodyresponsefrequentlyoccursafterpneumococcalpneumoniaandisassociatedwithinvasivedisease
AT riesbeckkristian nonfunctionalopsonicantibodyresponsefrequentlyoccursafterpneumococcalpneumoniaandisassociatedwithinvasivedisease