ZAP // DALL-E-2
Illustration of monocytes fighting a cancerous tumor.
Surprising discovery reveals that severe COVID-19 infection can shrink tumors by producing a special type of monocytes with unique anti-cancer properties.
A new study, on November 15th at Journal of Clinical Investigationreveals a potential unexpected benefit of severe COVID infection: may help reduce cancer.
The surprising discovery, based on research in mice, opens up new possibilities for treating cancer and sheds light on the complex interactions between the immune system and cancer cells — but it doesn’t mean people should actively try to catch COVID, researchers stress. .
The study focused on a type of white blood cell called monocyteimmune cells that play a crucial role in defending the body against infections and other threats.
However, in cancer patients, monocytes can sometimes be hijacked by tumor cells and transformed into cancer-friendly cells that protect the tumor from the immune system.
Researchers have found that a severe COVID infection causes the body to produce a special type of monocytes with properties unique anti-cancer.
These “induced” monocytes are specifically trained to attack the virus, but also retain the ability to fight cancer cells.
The key in the lock: “the perfect fit”
To understand how it all works, we have to look at the genetic material of the virus that gives rise to COVID. The researchers discovered that these induced monocytes have a special receptor that binds to a disease-specific sequence of RNA.
Ankit Bharat, one of the scientists involved in this work at Northwestern University in Chicago, explained this relationship using the key and lock analogy: “if the monocyte were a lock and COVID RNA was a key, then COVID RNA is the perfect fit“.
To test their theory, the research team performed experiments on mice with several types of advanced (stage 4) cancer, including melanoma, lung, breast and colon cancer. They gave the mice a drug that mimicked the immune response to a severe COVID infection, inducing the production of these special monocytes. Os results were remarkable.
The mice’s tumors began to shrink in all four types of cancer studied.
Unlike normal monocytes, which can be converted by tumors into protective cells, these induced monocytes retained their cancer-fighting properties. Were able to migrate to tumor sites — a feat that most immune cells cannot perform — and once there, they activated natural killer cells.
These killer cells then attacked the cancer cells, causing the tumors to shrink.
Kill tumors without relying on T cells
The newly discovered mechanism is particularly interesting because it offers a new approach to fighting cancer that does not rely on cancer, which are the focus of many current cancer treatments. immunotherapy.
Although immunotherapy has shown promise, it only works in about 20% to 40% of cases, often failing when the body cannot produce enough, functional T cells. In fact, dependence on T cell immunity is thought to be one of the main limitations of current immunotherapy approaches.
This new mechanism, instead, offers a way to selectively kill tumors that is independent of T cells, potentially providing a solution for patients who do not respond to traditional immunotherapy.
It is important to note that this study was carried out in rats and that clinical trials will be needed to determine whether the same effect occurs in humans.
While COVID vaccines are unlikely to trigger this mechanism (since they do not use the full RNA sequence of the virus), the research opens up possibilities for developing new drugs and vaccines that could stimulate the production of these cancer-fighting monocytes.
But the implications of this study go beyond COVID and cancer.
Trained immunity
The study also shows how our immune systems can be trained by one type of threat to become more effective against another. This concept, known as “trained immunity,” is an exciting area of research that could lead to new approaches to treating a wide range of diseases.
However, it is essential to emphasize once again that this does not mean that people should seek out COVID infection as a way to fight cancer, which is particularly dangerous. THE Severe COVID can be fatal and has many serious long-term health consequences.
