German Research Foundation DFG Extends Funding to Support Innovative T Cell Mitochondrial Research

During the first phase, the team made a major discovery: bone marrow–derived stromal cells can transfer their mitochondria, the organelle powerhouses of the cell, directly into CD8⁺ T cells, the key cancer-busting cells of the immune system. Using advanced microscopy, the researchers demonstrated that these donated mitochondria are structurally intact and become integrated into recipient T cells. This process dramatically boosts T-cell metabolism, survival, and resistance to exhaustion. In mouse models of melanoma, T cells that received mitochondria infiltrated tumors more efficiently and showed far stronger antitumor activity than conventional T cells. The researchers demonstrated proof-of-concept in human clinical applications with CAR T cells and tumor-infiltrating lymphocytes (TILs): receiving donor mitochondria demonstrated increased killing capacity even after repeated challenges, resulting in more effective control against leukemia and melanoma. These findings were published in one of the top journals in the field, Cell, and introduced a completely new way to reprogram immune cells by upgrading their metabolic machinery.

With continued support of the German Research Foundation (DFG, Deutsche Forschungsgemeinschaft) now secured, the project enters its second phase, shifting from discovery to detailed mechanistic insight and clinical translation. Using newly developed genetically engineered mouse models, the researchers will determine where and when mitochondrial transfer occurs in living organisms and how it shapes T-cell memory and long-term immune protection. At the molecular level, advanced spatial proteomics and gene-editing approaches will be used to identify and manipulate the proteins that form the tiny cellular bridges, known as tunneling nanotubes, that allow mitochondria to move between cells. With continued funding now in place, this pioneering research moves one step closer to transforming how immune cells are engineered to fight cancer.