RAD51 Stabilises Neutrophil Extracellular Traps and Keeps Inflammation Localized: Science | August 2026

Neutrophil extracellular traps (NETs) are DNA-rich webs released by neutrophils to capture pathogens, but excessive NET activity can also promote inflammation. This study identifies an unexpected role for the DNA-repair protein RAD51 in creating the branched chromatin architecture that stabilizes NETs and, importantly, helps confine inflammation to infected tissues.

Why was this study needed?

NETs can be both antimicrobial and proinflammatory.

The mechanism responsible for their highly branched DNA architecture was unknown.

Destabilizing NETs has been considered a potential anti-inflammatory strategy.

It remained unclear whether NET structure itself controls the transition from localized to systemic inflammation.

Results:

RAD51 generated branched DNA structures that stabilized NET chromatin and made NETs more resistant to degradation.

Blocking RAD51 reduced NET branching and accelerated NET breakdown.

Surprisingly, during pulmonary Aspergillus infection, destabilizing NETs did not improve disease; instead, NET-derived DNA accumulated in the circulation.

Circulating NET fragments activated monocytes and increased IL-6, amplifying Th17/type 2 inflammation, eosinophilia, mucus production, and airway obstruction.

Clinical Impact:

The study changes the concept of NETs from simply inflammatory structures to potential spatial barriers that compartmentalize inflammation. Therapeutically dismantling NETs may therefore have unintended consequences: reducing local inflammation while releasing inflammatory chromatin into the systemic circulation.

The findings also establish an unexpected mechanistic connection between DNA-repair machinery, innate immunity, and inflammatory disease.

Bottom Line:

RAD51-mediated DNA branching acts as a structural “scaffold” that stabilizes NETs and keeps inflammation localized. Disrupting NET architecture can paradoxically worsen systemic inflammation through circulating DNA and IL-6—suggesting that future NET-targeted therapies must consider not only NET formation, but also where their inflammatory contents go after NET breakdown.