Several French public research institutions have announced the temporary suspension of prion research after a former Institut National de la Recherche Agronomique (Inrae) researcher that worked with prions developed symptoms of Creutzfeldt-Jakob disease.
Creutzfeldt-Jakob disease has similar symptoms to mad cow disease in cattle.
The decision was jointly taken by Anses, CEA, CNRS, Inrae, and Inserm, and supported by the French Ministry of Higher Education, Research and Innovation. As of 27 July 2021, French laboratories have temporarily suspended prion research for three months.
The precautionary measure was taken following the discovery of a possible case of Creutzfeldt-Jakob disease by a former Inrae researcher working on prions. In this individual, there could be several causes to his brain degeneration: genetic, accidental, or iatrogenic, i.e. infection by a contaminated instrument. So far the type contracted by the former researcher is not yet known.
This is not a unique case. In 2019, an assistant engineer died of Creutzfeldt-Jakob disease. She was infected in 2010 as a result of an injury sustained during an experiment. An investigation following this case led to the conclusion that “the laboratories inspected were in compliance with the rules”, Inserm wrote in a press release.
Prions are proteins that act as infectious agents
Creutzfeldt-Jakob disease is caused by a prion protein (PrPc) that is expressed in many cells in the body. In its healthy, active form, it is structured as an alpha helix. However, it can also be present in a pathological form consisting of beta helices. It is then called PrPcsc or scrapie.
In this form, it clusters in cells and can convert healthy prion proteins into scrapie by transferring their abnormal structure. This infectious agent is the only one known not to contain nucleic acids, the building blocks of DNA and RNA.
Scrapie accumulates slowly, with adverse effects occurring several years after infection. Diagnosis is difficult and prion diseases are often confirmed only after death. Once the first symptoms appear, the disease progresses rapidly until the patient dies. There is no specific treatment and doctors can only relieve the symptoms.