THE ESSENTIAL
- Our immune responses depend on both our genes and our life experiences, according to a new study.
- In this work, researchers have developed a map of the epigenetic modifications left by these two factors on our immune cells.
- In the future, this discovery could enable the development of more personalized treatments to combat infectious diseases.
When it comes to health, we are not all equal. But why? A study published in the journal Nature Genetics offers an answer. During their work, the researchers succeeded in mapping how genes and life experiences influence the functioning of immune cells.
The impact of genes and life experiences on immune cells
Life experiences include exposure to the environment, infections, or vaccines. “Our immune cells keep track of our genes and our experiences, and these two influences shape the immune system in very different ways.”explains Joseph Ecker, lead author of the study, in a communiqué.
In our cells, these influences translate into small molecular changes called epigenetic modifications. These can activate or deactivate the genes present in our cells and thus modify the way in which our cells function.
“This work shows that infections and environmental exposures leave lasting epigenetic imprints that influence the behavior of immune cells, continues Joseph Ecker. By analyzing these effects on a cell-by-cell basis, we can begin to link genetic and epigenetic risk factors to the specific immune cells where the disease actually originates..”
To do this, scientists analyzed blood samples from 110 people with very different genetic profiles and life experiences: vaccination, exposure to pesticides, different types of infections (flu, HIV, SARS-CoV-2, etc.). Result: inherited epigenetic modifications and those acquired throughout life do not act in the same way. The former regulate stable and long-lasting immune programs, such as those of T lymphocytes, while the latter influence more flexible regions of the genome, involved in rapid responses to infections. These differences could explain why some people develop more severe forms of infectious diseases.
Towards more individualized treatments for infections
In this study, researchers created an epigenetic atlas, a map of the modifications left by genes and experiences on immune cells. Ultimately, this tool could make it possible to better predict the evolution of an infection in a patient and to design personalized prevention or treatment strategies, adapted to each person’s immune profile.
“Our work lays the foundations for developing personalized prevention strategies against infectious diseases, concludes Wenliang Wang, another author. For Covid-19, the flu or many other infections, we may one day be able to predict how a person will respond to an infection, even before they are exposed.”
