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MUHC researchers have defined genetic resistance to the widespread virus, cytomegalovirus (CMV) — a member of the viral group that causes some of the world's most prevalent diseases, such as herpes, chicken pox and mononucleosis. The groundbreaking research, published in Nature Genetics last week, provides a roadmap for the development of human therapies for CMV, which could prolong the life of HIV patients and improve the success of transplant surgery by reducing the risk of rejection. There is currently no treatment or cure for CMV.

Resistance to diseases like CMV depends, at least partially, on the ability of our body's defense mechanism to recognize and destroy them. "Detecting these pathogens is not always easy," says Dr. Silvia Vidal, a Canada Research Chair in Host Response to Virus Infection based at the MUHC and lead author of the new research. "CMV has developed cunning disguises to avoid detection by our Natural Killer cells — one of several cell types that hunt down and terminate unwelcome invaders within our body." Our Natural Killer cells and the pathogens they fight have been locked in an evolutionary arms race for millions of years in an attempt to overwhelm each other.

Dr. Vidal and her team have spent the past 10 years studying CMV-resistant mouse strains in an attempt to describe the nature of their genetic resistance. "This research marks our second discovery of genetic resistance to CMV," she says. Most significantly, this new research documents an entirely new mechanism of resistance to CMV, involving the interaction between two genes. One gene flags virus-infected cells for destruction, the other gene allows our Natural Killer cells to recognize and terminate them. "This is a new concept in natural disease resistance," notes Dr. Vidal. "Our research suggests there are many different mechanisms for fighting viruses; in the future we expect to discover additional resistant genotypes."

CMV infects most of the world's organisms, including upwards of 80% of the human population. Although healthy people suffer only mild symptoms, infection can trigger fatal reactions in those with a compromised immune system, such as organ transplant recipients, newborns and persons infected with human immunodeficiency virus (HIV). Dr. Vidal believes her groundbreaking discovery increases the likelihood that therapies will be developed to fight CMV.

The Research Institute of the ³ÉÈËVRÊÓƵ Health Centre (RI MUHC) is a world-renowned biomedical and health care hospital research centre. Located in Montreal, Quebec, the institute is the research arm of the MUHC, a university health centre affiliated with the Faculty of Medicine at ³ÉÈËVRÊÓƵ. The institute supports over 500 researchers, nearly 1,000 graduate and postdoctoral students, and operates more than 300 laboratories devoted to a broad spectrum of fundamental and clinical research. The Research Institute operates at the forefront of knowledge, innovation and technology and is inextricably linked to the clinical programs of the MUHC, ensuring that patients benefit directly from the latest research-based knowledge. For further details visit .

The ³ÉÈËVRÊÓƵ Health Centre (MUHC) is a comprehensive academic health institution with an international reputation for excellence in clinical programs, research and teaching. The MUHC is a merger of five teaching hospitals affiliated with the Faculty of Medicine at ³ÉÈËVRÊÓƵ — the Montreal Children's, Montreal General, Royal Victoria and Montreal Neurological Hospitals, as well as the Montreal Chest Institute. Building on the tradition of medical leadership of the founding hospitals, the goal of the MUHC is to provide patient care based on the most advanced knowledge in the health care field, and to contribute to the development of new knowledge.