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Sequencing of Bacterial Microflora in Peripheral Blood: our Experience with HIV-infected Patients
Published on: June 11, 2011
The origin of circulating microbial DNA in the blood: where does it come from?
Zichen Zhang1, Wenbo Ren1, Yifei Wang2
1Department of Clinical Laboratory, The First Hospital of Jilin University, Changchun, China.
Background:
Circulating microbial DNA (cmDNA) is a significant biomarker involved in normal physiology, immunity, disease diagnosis, and pathogenesis. Its origin in peripheral blood has sparked extensive discussions and generated numerous hypotheses.
Aim:
This review explores four potential sources of cmDNA in the blood and analyzes research limitations and future prospects.
Results:
Four potential sources are collated and analyzed: exogenous microbes or DNA entering the peripheral blood after barrier damage; residual pathogen DNA remaining after infectious diseases; microbial translocation from sites such as the oral and intestinal mucosa into the bloodstream; and the extracellular vesicle delivery system, where microorganisms release vesicles to transfer DNA.
Conclusions:
The potential sources of cmDNA in the blood are not mutually exclusive and may be multifaceted, depending on an individual's health condition, sampling time, and contamination control. In-depth study of these sources will open new avenues for early disease detection, precise diagnosis, and prognosis assessment, and encourage further exploration in this promising field.
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