Scientists capture 3D view of killer T cells attacking cancer with molecular precision

For decades, science knew the immune system's killer T cells could destroy cancer with surgical precision — but could not truly witness the act. Now, researchers in Geneva and Lausanne have used a technique called cryo-expansion microscopy to freeze and expand human cells without distorting them, producing the first nanometer-scale, three-dimensional images of T cells attacking tumors in real human tissue. What emerges is not merely a clearer picture, but a new vocabulary for understanding why some immune responses succeed and others fail — a question that sits at the heart of modern cancer tr