Claude Perreault and his team study the cells governing the function of the immune system, called “T lymphocytes”, in order to understand and improve the function of the immune system. One of the aims of their research is to create a cancer vaccine and prevent the ageing of the immune system.

Research theme

The medical importance of immunology is considerable since infections represent the most common cause of death in humans. Dr. Claude Perreault strives to discover why the thymus is the sole organ that is able to support T lymphocytes development and how T lymphocytes learn, in the thymus, to distinguish self from non-self. Finally, he seeks to understand how T lymphocytes can recognize cancer cells and how one can increase the anti-tumor activity of T lymphocytes.

Cancer is caused by genetic mutations and the survival of cancer cells is dependent on these mutations, which often involve the production of abnormal proteins that can be detected by T lymphocytes to activate an immune response against the cancer cells. We now know that the more immune cells the tumor houses, the more favourable the patient’s prognosis.

For several types of cancer, exploratory work has shown that tumor regression could be observed following the injection of a “non-specific” stimulant (i.e., not directed at a particular molecule). Although more often than not the regression is partial, complete remission is sometimes noted. This requires that “foreign” molecules, called “cancer-specific antigens” (CSA), first be recognized by the immune cells (the T lymphocytes) which then eliminate the cancer cells. Understanding the origin of human CSA and the definition of their molecular composition would then pave the way for developing a vaccine against certain cancers.

The research work conducted by Dr. Perreault’s laboratory and his collaborators has resulted in the development of an approach that combines genomics, bioinformatics and proteomics, thanks to which they have identified the largest repertoire of tumor-specific antigens. That work has also brought to light the key factors that can influence the ability of the antigens to induce strong anti-tumor responses and provides hope for the development of a therapeutic vaccine against several cancers.

Research objectives

Acute myeloid leukemia is one of the most malignant forms of cancer. Although AML is complex, the effect and efficacy of a potential treatment for countering the evolution of the disease are quickly observed, notably by the daily quantification of the number of cancer cells.

After identifying the markers present on the surface of the leukemic cells that could also be recognized by the immune system, Dr. Perreault’s team developed a therapy that uses those markers to teach the T cells of a donor to recognize and destroy the cancer cells of a receiver during a transplant to treat leukemia.

This approach, currently in clinical trials in several hospitals, will make leukemia treatment more effective. Over the longer term, it could be extended to other types of cancer and pave the way to developing real cancer vaccines.