Branch Lab Translational Cell Therapy (Hannover)


Ex vivo expansion of PBMC-derived human NK cells for use in in vivo studies

Schematic depiction of a cancer cell identified and attacked by immune cells
© Christoph Burgstedt -
Schematic depiction of a cancer cell identified and attacked by immune cells.

One of the main functions of the human immune system is to defend against infections. Another is to eliminate cancer cells.

Immune cells are fundamentally capable of recognizing cancer cells and eliminating them through various mechanisms. One of these mechanisms is antibody-dependent, cell-mediated cytotoxicity (ADCC), whereby antibodies bind to the surface of cancer cells, giving natural killer (NK) cells a signal to kill the respective cells. These immune cells bind to the cancer cells via the antibodies and are stimulated to release cytotoxic proteins.

Despite some cancer cells being able to evade this mechanism due to their immunosuppressive properties, it offers an excellent starting point for developing new forms of cancer therapy based on this immunological principle.

To this end, the company Affimed developed a new antibody platform for killing malignant target cells with extreme precision. This platform enables the immunosuppressive mechanisms employed by tumor cells are overcome and a targeted immune response to be triggered.

As part of the project, leukapheresis was conducted on different, healthy donors at Fraunhofer IZI’s off-site unit in Hannover. NK cells were then separated immunomagnetically from the enriched peripheral blood mononuclear cells (PBMCs), expanded for two ex vivo weeks, and then cryopreserved. The cells could then be thawed, expanded / activated anew and investigated as part of preclinical tests as and when required.