Cargando…

Plasma cfDNA predictors of established bacteraemic infection

Introduction. Increased plasma cell-free DNA (cfDNA) has been reported for various diseases in which cell death and tissue/organ damage contribute to pathogenesis, including sepsis. Gap Statement. While several studies report a rise in plasma cfDNA in bacteraemia and sepsis, the main source of cfDNA...

Descripción completa

Detalles Bibliográficos
Autores principales: Urosevic, Nadezda, Merritt, Adam J., Inglis, Timothy J. J.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Microbiology Society 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9394668/
https://www.ncbi.nlm.nih.gov/pubmed/36004363
http://dx.doi.org/10.1099/acmi.0.000373
_version_ 1784771529253322752
author Urosevic, Nadezda
Merritt, Adam J.
Inglis, Timothy J. J.
author_facet Urosevic, Nadezda
Merritt, Adam J.
Inglis, Timothy J. J.
author_sort Urosevic, Nadezda
collection PubMed
description Introduction. Increased plasma cell-free DNA (cfDNA) has been reported for various diseases in which cell death and tissue/organ damage contribute to pathogenesis, including sepsis. Gap Statement. While several studies report a rise in plasma cfDNA in bacteraemia and sepsis, the main source of cfDNA has not been identified. Aim. In this study, we wanted to determine which of nuclear, mitochondrial or bacterial cfDNA is the major contributor to raised plasma cfDNA in hospital subjects with bloodstream infections and could therefore serve as a predictor of bacteraemic disease severity. Methodology. The total plasma concentration of double-stranded cfDNA was determined using a fluorometric assay. The presence of bacterial DNA was identified by PCR and DNA sequencing. The copy numbers of human genes, nuclear β globin and mitochondrial MTATP8, were determined by droplet digital PCR. The presence, size and concentration of apoptotic DNA from human cells were established using lab-on-a-chip technology. Results. We observed a significant difference in total plasma cfDNA from a median of 75 ng ml(−1) in hospitalised subjects without bacteraemia to a median of 370 ng ml(−1) (P=0.0003) in bacteraemic subjects. The copy numbers of nuclear DNA in bacteraemic also differed between a median of 1.6 copies µl(−1) and 7.3 copies µl(−1) (P=0.0004), respectively. In contrast, increased mitochondrial cfDNA was not specific for bacteraemic subjects, as shown by median values of 58 copies µl(−1) in bacteraemic subjects, 55 copies µl(−1) in other hospitalised subjects and 5.4 copies µl(−1) in healthy controls. Apoptotic nucleosomal cfDNA was detected only in a subpopulation of bacteraemic subjects with documented comorbidities, consistent with elevated plasma C-reactive protein (CRP) levels in these subjects. No bacterial cfDNA was reliably detected by PCR in plasma of bacteraemic subjects over the course of infection with several bacterial pathogens. Conclusions. Our data revealed distinctive plasma cfDNA signatures in different groups of hospital subjects. The total cfDNA was significantly increased in hospital subjects with laboratory-confirmed bloodstream infections comprising nuclear and apoptotic, but not mitochondrial or bacterial cfDNAs. The apoptotic cfDNA, potentially derived from blood cells, predicted established bacteraemia. These findings deserve further investigation in different hospital settings, where cfDNA measurement could provide simple and quantifiable parameters for monitoring a disease progression.
format Online
Article
Text
id pubmed-9394668
institution National Center for Biotechnology Information
language English
publishDate 2022
publisher Microbiology Society
record_format MEDLINE/PubMed
spelling pubmed-93946682022-08-23 Plasma cfDNA predictors of established bacteraemic infection Urosevic, Nadezda Merritt, Adam J. Inglis, Timothy J. J. Access Microbiol Research Articles Introduction. Increased plasma cell-free DNA (cfDNA) has been reported for various diseases in which cell death and tissue/organ damage contribute to pathogenesis, including sepsis. Gap Statement. While several studies report a rise in plasma cfDNA in bacteraemia and sepsis, the main source of cfDNA has not been identified. Aim. In this study, we wanted to determine which of nuclear, mitochondrial or bacterial cfDNA is the major contributor to raised plasma cfDNA in hospital subjects with bloodstream infections and could therefore serve as a predictor of bacteraemic disease severity. Methodology. The total plasma concentration of double-stranded cfDNA was determined using a fluorometric assay. The presence of bacterial DNA was identified by PCR and DNA sequencing. The copy numbers of human genes, nuclear β globin and mitochondrial MTATP8, were determined by droplet digital PCR. The presence, size and concentration of apoptotic DNA from human cells were established using lab-on-a-chip technology. Results. We observed a significant difference in total plasma cfDNA from a median of 75 ng ml(−1) in hospitalised subjects without bacteraemia to a median of 370 ng ml(−1) (P=0.0003) in bacteraemic subjects. The copy numbers of nuclear DNA in bacteraemic also differed between a median of 1.6 copies µl(−1) and 7.3 copies µl(−1) (P=0.0004), respectively. In contrast, increased mitochondrial cfDNA was not specific for bacteraemic subjects, as shown by median values of 58 copies µl(−1) in bacteraemic subjects, 55 copies µl(−1) in other hospitalised subjects and 5.4 copies µl(−1) in healthy controls. Apoptotic nucleosomal cfDNA was detected only in a subpopulation of bacteraemic subjects with documented comorbidities, consistent with elevated plasma C-reactive protein (CRP) levels in these subjects. No bacterial cfDNA was reliably detected by PCR in plasma of bacteraemic subjects over the course of infection with several bacterial pathogens. Conclusions. Our data revealed distinctive plasma cfDNA signatures in different groups of hospital subjects. The total cfDNA was significantly increased in hospital subjects with laboratory-confirmed bloodstream infections comprising nuclear and apoptotic, but not mitochondrial or bacterial cfDNAs. The apoptotic cfDNA, potentially derived from blood cells, predicted established bacteraemia. These findings deserve further investigation in different hospital settings, where cfDNA measurement could provide simple and quantifiable parameters for monitoring a disease progression. Microbiology Society 2022-06-14 /pmc/articles/PMC9394668/ /pubmed/36004363 http://dx.doi.org/10.1099/acmi.0.000373 Text en © 2022 The Authors https://creativecommons.org/licenses/by/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution License. This article was made open access via a Publish and Read agreement between the Microbiology Society and the corresponding author’s institution.
spellingShingle Research Articles
Urosevic, Nadezda
Merritt, Adam J.
Inglis, Timothy J. J.
Plasma cfDNA predictors of established bacteraemic infection
title Plasma cfDNA predictors of established bacteraemic infection
title_full Plasma cfDNA predictors of established bacteraemic infection
title_fullStr Plasma cfDNA predictors of established bacteraemic infection
title_full_unstemmed Plasma cfDNA predictors of established bacteraemic infection
title_short Plasma cfDNA predictors of established bacteraemic infection
title_sort plasma cfdna predictors of established bacteraemic infection
topic Research Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9394668/
https://www.ncbi.nlm.nih.gov/pubmed/36004363
http://dx.doi.org/10.1099/acmi.0.000373
work_keys_str_mv AT urosevicnadezda plasmacfdnapredictorsofestablishedbacteraemicinfection
AT merrittadamj plasmacfdnapredictorsofestablishedbacteraemicinfection
AT inglistimothyjj plasmacfdnapredictorsofestablishedbacteraemicinfection