An interdisciplinary team of scientists from Otto von Gerike University Magdeburg has uncovered new insights into how mediators of inflammatory defenses against pathogens can remotely trigger cancer cell death – an important contribution to improving cancer immunotherapy.

Modern immunotherapy enhances the body’s natural ability to fight cancer by activating killer T cells of the immune system, which can specifically target and destroy cancer cells. However, many patients develop cancer cells and become undetectable by these T cells, rendering treatment ineffective.

An interdisciplinary research team from Magdeburg has discovered a new mechanism that allows the immune system to eliminate such invisible cancer cells as well. These discoveries offer new opportunities for the development of advanced cancer immunotherapy. The results were published in a well-known journal. Nature.

“In our study, we looked for strategies to target such cancer cells that are ‘invisible’ for killer T cells. Professor of dermatology at Magdeburg University Hospital and head of the research team.

Microscopic image of cancer-fighting helper T cells (turquoise) and killer T cells (red) (shown in blue). Killer T cells must migrate to large numbers of cancer tissues for an effective immune defense against cancer. The study, published in Nature, shows, by contrast, that helper T cells stay at the edges of cancerous tissues, where they direct the remote death of cancer cells. This requires far fewer helper T cells than killer T cells. Both images were created using intravital 2-photon microscopy, which allows to observe the behavior of immune cells in living tissue. Credit: Otto von Gerike University of Magdeburg

Few helper T cells are more effective than many killer T cells.

Using an experimental cancer model, the researchers observed that few helper T cells were able to destroy common cancers as effectively as much more killer T cells. Helper T cells were also able to destroy cancer cells that had become invisible by the killer T cells.

Using advanced microscopy techniques to examine immune cells in living cancer tissue has revealed that helper T cells behave fundamentally differently from killer T cells: “Killer T cells penetrate cancer tissues and interact directly with cancer cells, while Helper T cells are mainly located at the edge. University of Magdeburg Molecular and Professor of Clinical Immunology Institute.

Helper T cells recruit scavenger cells and remotely direct cancer cell death through inflammatory mediators of pathogen defense

Further research showed that helper T cells secrete chemical mediators that attract scavenger cells of the immune system and encourage them to support the destruction of cancer cells on their behalf. Together, these two types of cells can effectively fight bacterial and viral infections. The collaboration can also be used to mobilize the entire immune defense arsenal against cancer cells.

Investigating the underlying mechanisms of action, the researchers discovered that the interaction between helper T cells and scavenger cells increases their ability to release remotely acting inflammatory mediators, causing cancer cells to die as if infected with a pathogen. Exactly how this happens is still poorly understood, and the importance of this mechanism for cancer immunotherapy will need to be clarified.

Prospects for new ways to improve cancer immunotherapy

The results of the study reveal the mechanism by which the immune system’s ability to defend itself against the spread of pathogens in the body can be used to destroy cancer cells. Based on these findings, Magdeburg researchers are developing new cancer immunotherapy strategies that are also effective in patients with cancers that have become invisible to killer T cells. Source