What if an infection as serious as sepsis could ultimately protect the patient against the development of cancer ? This is the unexpected hypothesis suggested by French researchers from Inserm. Focus on the conclusions of their new study.
What is sepsis?
The sepsis refers to generalized inflammationand massive, causing a dysfunction in the body that can be fatal. It is usually associated with a serious bacterial or viral infection such as influenza or Covid-19.
To know! 57,000 people die from sepsis each year in France.
If inflammatory states are rather documented in the scientific literature as constituting risk factors for cancer, French researchers nevertheless suggest in a new study that patients who survive sepsis could then be protected against the development of tumors .
Sepsis: protection against cancer?
To carry out their work, the researchers relied on health data from more than 110,000 French people hospitalized between 2010 and 2016. Within this panel:
- 50% of patients suffered from sepsis.
- 50% of patients with a less serious infection.
The researchers then noted that for equivalent risk factors (age, sex, obesity, etc.), the patients with sepsis had an average 12.5% reduced risk of developing cancer compared to patients suffering from a less serious infection!
Faced with this astonishing correlation, the scientists’ objective was then to demonstrate whether a real link existed between the occurrence of an episode of sepsis and a potential protective effect against cancer in these patients. Thus, several cellular and molecular biology studies have been carried out in animals to understand the mechanisms involved in this unexpected protective effect.
In particular, they were able to observe that in mice suffering from sepsis, certain immune cells called macrophages were “trained” to react quickly to a new infection. These cells then produce small proteins called chemokines responsible for attracting and retaining other immune cells (resident T cells) in the affected organs. And, remarkably, these immune cells persist in the tissues concerned for several weeks or months after recovery from sepsis!
According to the lead author of this study, the persistent presence of macrophages and persistent resident T cells would thus contribute to increasing anti-tumor immune surveillance and promote a faster and more effective response in the event of the development of cancer.
How can we imitate the “protective” effects of sepsis?
Therefore, it seemed interesting to the team of researchers to try to pharmacologically reproduce this immunity induced by sepsis. They thus used “beta-glucan” which they injected into a population of mice.
To know! Coming from brewer’s yeast, “beta-glucan” refers to a soluble fiber known for its ability to activate macrophages.
Following this injection, the mice’s macrophages were able to react quickly and allow the recruitment of resident T cells, exactly as following sepsis. Hence the idea of applying this principle to humans. The only downside is that beta-glucan fiber is currently not sufficiently purified and therefore presents a potential risk to human health. Hence the need for researchers to identify the minimal active part essential for the macrophage-stimulating activity of beta-glucan in order to be able to use it in humans.
If research on the subject still needs to progress, the authors of this study published in the excellent international scientific journal Nature immunology are hopeful that their work could one day lead to the development of therapeutic strategies aimed at preventing and treating cancers.
Sources
– The anti-cancer properties of sepsis. . www.lequotidiendupharmacien.fr. Accessed October 26, 2024.
– Severe infections: A shield against cancer? . www.inserm.fr. Accessed October 26, 2024.
Written by Déborah L.
