Tuesday, May 05, 2026

T cells secrete extracellular vesicular DNA to help immune system fight cancer

Good news! Cancer is history (soon)!

"Activated immune cells secrete tiny capsules bearing DNA that can enter other immune and tumor cells to stimulate the body’s defense systems, according to a study ...

The discovery extends the scientific understanding of the immune system, identifies a new strategy for boosting immunity against cancers and potentially offers a new tool for delivering genetic payloads to other cells. ...

In the new study ... the researchers discovered that [extracellular] vesicles secreted by activated T cells – major weapons of the immune system – carry DNA that enters immune cells and nearby tumor cells to enhance the immune response against the tumor.
Preclinical experiments showed that this vesicle-associated DNA could be useful therapeutically, boosting T cell attacks against tumors that otherwise evoke little or no immune response. ..."

From the highlights and abstract:
"Highlights
• Activated T cells secrete abundant extracellular vesicular DNA (AT-EVDNA)
• AT-EVDNA is mainly from newly made genomic DNA rich in immune-related gene content
• ATEVs boost antigen presentation via EVDNA intranuclear transfer aided by granzyme B
• ATEVs act as acellular immunotherapy to overcome tumor immune evasion

Summary
Antigen processing and presentation (APP) is essential for adaptive immunosurveillance.
We uncover a mechanism whereby activated T cell-derived extracellular vesicles (ATEVs) drive a positive feedback loop that enhances antigen presentation and immune responses in normal physiology and cancer.
ATEV-induced immunogenicity relies on extracellular vesicular double-stranded DNA (EVDNA), which is notably abundant and primarily composed of genomic DNA enriched in immune-related genes, including those encoding APP machinery.
Mechanistically, granzyme B (Gzmb) packaged by ATEVs disrupts the nuclear envelope of recipient cells, facilitating intranuclear transfer and subsequent transient expression of EVDNA encoding APP genes.
DNase treatment removes most AT-EVDNA, abrogating APP upregulation and thus T cell activation and recruitment to tumors.
Notably, ATEVs hold promise as an acellular immunotherapy, restoring APP and synergizing with checkpoint blockade in immunotherapy-refractory tumors. Collectively, our findings uncover a mechanism of transient, non-viral gene delivery by ATEVs that boosts APP and anti-tumor immunity while limiting autoimmunity."

T cells secrete DNA to help immune system fight cancer | Cornell Chronicle



Graphical abstract


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