Cell-free DNA in plasma as an essential immune system regulator

Area of Science:

• Immunology
• Molecular Biology
• Biochemistry

Background:

• Cell-free DNA (cfDNA) is a biomarker of interest in diagnostics and therapy monitoring.
• The physiological role of cfDNA in healthy individuals remains largely unexplored.

Purpose of the Study:

• To investigate the physiological role of cfDNA in plasma.
• To determine how cfDNA presence and clearance impact immune system regulation and homeostasis.

Main Methods:

• THP1 cells were treated with plasma containing (NP) and lacking (TP) cfDNA.
• Gene expression analysis was performed to assess cellular responses.
• Mass spectrometry was used to identify protein abundance changes.

Main Results:

• Plasma with cfDNA (NP) upregulated genes involved in immune homeostasis.
• Plasma without cfDNA (TP) induced an innate immune response (IIR), including elevated interleukin-8 expression.
• Mass spectrometry revealed increased proteins associated with IIR activation and complement cascade regulation in TP-treated cells.

Conclusions:

• cfDNA presence and clearance in plasma are vital for immune system regulation.
• cfDNA influences inflammation and tissue homeostasis by modulating immune responses.
• Understanding cfDNA's role, particularly related to neutrophil extracellular traps, has significant medical applications.