Tel Aviv University team shows how tumours turn the immune system's cleaners into allies

Scientists at Tel Aviv University have uncovered how cancers recruit some of the body's own immune cells to help them grow. The study, led by Dr Merav Cohen with doctoral students Roi Balaban and Ori Moskowitz, was published in Science Immunology in June 2026 and reported by JNS and the Tazpit Press Service on 3 July.

Macrophages are immune cells that patrol the body and clear away dead and damaged cells, a housekeeping job that keeps tissues healthy and limits inflammation. It has long been known that tumours can enlist macrophages, but not how ordinary macrophages are converted into tumour supporters. Cohen's team found that the switch begins when macrophages engulf dead cancer cells, a process called efferocytosis. Rather than simply digesting the debris, the cells change which genes they use.

To follow this, the researchers developed a technique they call Effero-seq, which identifies the macrophages that have eaten dead cancer cells and tracks how their gene activity changes over time. In a melanoma model, these reprogrammed macrophages switched on genes that build new blood vessels, which supply tumours with oxygen and nutrients, and became less responsive to signals that normally trigger an immune attack. When the team examined data from patients with uveal melanoma, a rare eye cancer, those whose tumours had more macrophages with this genetic signature generally had lower survival.

Cohen said future treatments might aim not only at cancer cells but at stopping immune cells from being reprogrammed, though the researchers caution that the idea is still experimental.