At the Max Delbrück Center in Berlin, researchers have given cancer-fighting immune cells a crucial upgrade: a better GPS system for finding tumors. Dr. Uta Höpken and her team, including postdoctoral researcher Dr. Maria Zschummel, engineered CAR-T cells to express the CCR7 receptor, a protein that acts like a navigation beacon, allowing the cells to penetrate lymph nodes and kill lymphoma cells far more effectively than before.
CAR-T therapy has already revolutionized treatment for blood cancers by reprogramming patients' own immune cells to recognize and destroy tumor cells. Many patients achieve long-lasting remission or even cure. Yet the approach still stumbles against lymphomas—cancers of the lymphatic system—especially when tumor cells hide within lymph nodes where CAR-T cells struggle to reach them.
The problem lies in how CAR-T cells are manufactured. During production, the cells lose expression of CCR7, the very receptor that guides immune cells into lymph node tissue under normal circumstances. It's as though the cells arrive at the airport but lose their map. Zschummel and Höpken solved this by permanently engineering CAR-T cells to express CCR7, restoring their natural homing ability. "If therapeutic immune cells cannot reach these sites efficiently, even powerful therapies may fail," Zschummel explains. "By restoring the receptor CCR7, we essentially gave the cells a better navigation system to find the tumor."
The researchers tested their modified CAR-T-CCR7 cells across multiple experiments using human immune cells, lymphoma cell lines, and mouse models. The results exceeded expectations. The enhanced cells regained the ability to migrate into lymph nodes and accumulated more efficiently once there. In mouse models, they eliminated lymphoma cells more effectively than conventional CAR-T cells. "We expected improved migration, but CCR7 also boosted the cells' killing efficiency," Zschummel recalls. "This was a surprise."
The findings, published in Cancer Immunology Research, suggest that improving immune cells' navigation system doesn't just help them find targets—it makes them more potent fighters. Höpken notes that the strategy could extend beyond lymphomas to other cancers that spread to lymph nodes, offering a more general principle for refining next-generation cell therapies. "We show that improving the 'navigation system' of immune cells can make them generally more effective fighters against cancer," she says.
Before patients can benefit, further clinical work lies ahead. Safety studies and long-term follow-up must precede any move to human trials. Yet the research illuminates something vital about immunotherapy's future: that basic immunology—decades of studying how immune cells naturally navigate the body—can directly translate into more powerful treatments. In an era where cell therapy shows such promise yet still fails too often, giving these cellular soldiers the tools they need to reach their enemies could mean the difference between remission and relapse, between hope and heartbreak.
The paper, authored by Maria Zschummel and colleagues, was published in Cancer Immunology Research in 2026.