A virus scrutinized by the European project Horus

The European project Horus, aiming to improve the care of organ transplant recipients in the face of viral infections, has just launched on the Bordeaux campus and in various European countries.

  • 12/01/2023

Kidney, heart, lung and liver transplants will be studied as part of the Horus project © Grilled cheese / IHU Liryc Kidney, heart, lung and liver transplants will be studied as part of the Horus project © Grilled cheese / IHU Liryc

CMV for cytomegalovirus, this is the virus that researchers from the ImmunoConcEpT laboratory (CNRS and University of Bordeaux) have been tracking for nearly 20 years to better understand it. A virus from the varicella and herpes family, transmitted by bodily secretions (saliva, blood, tears, sexual, etc.) little known by the general public even if it is paradoxically very present in humans, its only reservoir.

It is true that CMV is responsible for infections that usually go unnoticed, even though it remains latent in the body for life when present. The virus must however be taken into account on certain occasions: for both pregnant women and immunocompromised people. This non-aggressiveness is dangerous in certain cases, making CMV a virus responsible for so-called opportunistic infections. And organ transplant patients are a target of choice.

This is the entire purpose of the European project led by Hannah Kaminiski, lecturer-researcher at the University of Bordeaux and ImmunoConcEpT, and nephrologist at Bordeaux University Hospital, who now leads a consortium of more than fifteen clinical and scientific partners in France and Europe (Spain, Germany, Italy, Switzerland, Czech Republic, Belgium, etc.).
Since the filing of a research project always requires finding a name and an appropriate acronym, the scientists here appealed to the eye of Horus for "Casting Light on HOst-cytomegaloviRUs interaction in Solid organ transplantation". The project, led by the University of Bordeaux, has been selected as part of the Horizon Europe "Tackling diseases" program and will benefit from 7 million euros of funding over the course of 5 years.

A European follow-up cohort of 450 patients

"CMV infections are the most frequent opportunistic infections in organ transplant patients, of which we are trying to improve our understanding on a fundamental level, while also trying to determine which patients are the most at risk based on their immune response", the researcher explains.

Several scenarios are possible for the organ transplant recepient to develop infections after the graft: either they were a carrier of the virus before the transplant, or the transplanted organ is a carrier of the virus and contaminates the recipient. Faced with shortages of transplants, the latter are not ruled out even if they are carriers.

"Otherwise, we would cancel one out of two transplants!" explains the researcher. The prospects are therefore to better manage infectious complications and avoid rejection. For this, the scientists want to create a follow-up cohort of 450 patients in Europe. While the Bordeaux research team specializes in kidney transplantation, the Horus project will also study heart, lung and liver transplants. Is it possible to predict when an infection will develop? Can an immunological signature be evaluated? We know for example that some people will never develop a CMV infection, even if they are immunocompromised, because they have a so-called innate or adaptive immunity to the virus. Is it possible to identify and use this immunity? Since antivirals can cause adverse effects in addition to anti-rejection treatments, can their use be adjusted according to the patient's profile? Can we therefore personalize the support provided? And beyond that, is it possible to identify a new therapeutic target for CMV?

These are all the questions that scientists will attempt to answer over the next few years. While deaths due to cytomegalovirus infections remain rare, the direct (digestive, pulmonary, neurological, etc.) and indirect effects (causing comorbidities) in organ transplant patients are sufficiently important to be taken into account within the framework of such a project (CMV infections are notably associated with an increased risk of rejection), which officially started early November 2022.


Hannah Kaminski
Horus project coordinator

Assistant Professor - Hospital Practitioner
Contact by email