Ahmad Yatim, post-doctoral fellow in immunology, won the 2021 Bettencourt Prize for Young Researchers for his work on resistance to SARS-CoV-2.

Pseudo-frostbite as a sign of unusual immunity

Since the beginning of the COVID-19 pandemic, a high number of inflammatory limb lesions resembling frostbite have been observed. The unusual rise in pseudo-frostbite cases suggests a link to SARS-CoV-2 infection. Surprisingly, despite close contact with infected individuals, people with pseudo-frostbite do not test positive for SARS-CoV-2 or develop COVID symptoms. Could there be a link between pseudo-frostbite and resistance to SARS-CoV-2 infection?

Severe forms of COVID seem to be related to a defect in the innate immune response (i.e. independent of antibody production), whose purpose is to slow down the advance of the virus to allow time for the adaptive immune response (antibodies) to start working. A very strong innate response could rapidly eliminate the virus on its own without requiring antibody production. The link between pseudo-frostbite and resistance to SARS-CoV-2 infection could be the development of an unusual innate immunity in these individuals, as the skin lesions result from high activity of interferon, a key mediator of the antiviral innate response.

SARS-CoV-2 resistance: the answer may be in our genes

In Jean-Laurent Casanova’s laboratory at Rockefeller University, Ahmad Yatim will aim to discover the genetic and molecular basis of interferon-mediated resistance to SARS-CoV-2. His hypothesis is that genetic factors predispose individuals to develop exceptional natural immune defenses against SARS-CoV-2, making them resistant to infection.

He will build an international cohort of people who developed pseudo-frostbite after exposure to SARS-CoV-2 and sequence their genomes to identify changes in genes that may explain their resistance. After identifying genes in the resistant patients, Dr. Yatim will experiment on cells to understand how they affect antiviral defenses.

Ahmad Yatim in a few words

During his PhD work in molecular and cellular biology under the supervision of Monsef Benkirane and Yves Levy at the Institute of Human Genetics in Montpellier, Ahmad Yatim was interested in a signaling pathway necessary for the development of T lymphocytes, cells found in the bloodstream that play a role in immune response. This pathway, called Notch, is disrupted in people with acute lymphoblastic leukemia.

Dr. Yatim's award-winning work has identified potential therapeutic targets in this cancer.

After completing his PhD in 2012, he began studying medicine at Université Paris-Est Créteil and specialized in dermatology in Switzerland.

During his post-doctoral fellowship in New York, Dr. Yatim will study how an intriguing skin sign can hide a mechanism of resistance to SARS-CoV-2 infection.

Bettencourt Prize for Young Researchers

Created in 1990, the Bettencourt Prize for Young Researchers is one of the first initiatives of the Fondation Bettencourt Schueller. Until 2021, this prize was awarded each year to 14 young doctors of science or doctors of medicine, to enable them to carry out their post-doctoral stay in the best foreign laboratories. 349 young researchers were distinguished. The prize endowment was €25,000.

All the award-winners