title: Comprehensive description of blood microbiome from healthy donors assessed by 16S targeted metagenomic sequencing.
abstract: Recent studies have revealed that the blood of healthy humans is not as sterile as previously supposed. The objective of this study was to provide a comprehensive description of the microbiome present in different fractions of the blood of healthy individuals.
  
  
  
  The study was conducted in 30 healthy blood donors to the French national blood collection center (Établissement Français du Sang). We have set up a 16S rDNA quantitative polymerase chain reaction assay as well as a 16S targeted metagenomics sequencing pipeline specifically designed to analyze the blood microbiome, which we have used on whole blood as well as on different blood fractions (buffy coat [BC], red blood cells [RBCs], and plasma).
  
  
  
  Most of the blood bacterial DNA is located in the BC (93.74%), and RBCs contain more bacterial DNA (6.23%) than the plasma (0.03%). The distribution of 16S DNA is different for each fraction and spreads over a relatively broad range among donors. At the phylum level, blood fractions contain bacterial DNA mostly from the Proteobacteria phylum (more than 80%) but also from Actinobacteria, Firmicutes, and Bacteroidetes. At deeper taxonomic levels, there are striking differences between the bacterial profiles of the different blood fractions.
  
  
  
  We demonstrate that a diversified microbiome exists in healthy blood. This microbiome has most likely an important physiologic role and could be implicated in certain transfusion-transmitted bacterial infections. In this regard, the amount of 16S bacterial DNA or the microbiome profile could be monitored to improve the safety of the blood supply.
authors: Vaiomer SAS, Labège.
authors: Sandrine
authors: S
authors: Païssé
authors: Vaiomer SAS, Labège.
authors: Carine
authors: C
authors: Valle
authors: Vaiomer SAS, Labège.
authors: Florence
authors: F
authors: Servant
authors: Vaiomer SAS, Labège.
authors: Michael
authors: M
authors: Courtney
authors: Vaiomer SAS, Labège.|INSERM U1048, I2MC, Toulouse.
authors: Rémy
authors: R
authors: Burcelin
authors: Vaiomer SAS, Labège.|Department of Therapeutics, Rangueil Hospital, Toulouse, France.
authors: Jacques
authors: J
authors: Amar
authors: Vaiomer SAS, Labège.
authors: Benjamin
authors: B
authors: Lelouvier
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001769:Blood / Q000382:microbiology*; D001782:Blood Donors; D058731:Blood Safety; D004269:DNA, Bacterial / Q000097:blood / Q000302:isolation & purification*; D004275:DNA, Ribosomal; D005602:France; D064368:Healthy Volunteers; D006801:Humans; D056186:Metagenomics / Q000379:methods*; D064307:Microbiota; D008875:Middle Aged; D010802:Phylogeny; D062486:Public Health Surveillance / Q000379:methods; D055815:Young Adult
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal