Grant: Project Grant

Cannabis is a plant that is commonly referred to as marijuana. Cannabis has been used for medicinal purposes for thousands of years. Canada will be one of the first countries in the world to legalize cannabis. Reports estimate that between 9-14% of Canadians use cannabis- a number that has doubled in the past 2 decades. With impending legalization, regular use is predicted to increase even more. Most people still use cannabis by inhalation of cannabis smoke. Other ways to now use cannabis is vaporizing the cannabis plant. This means the plant is heated but not burned like for smoke. Both ways in which cannabis is used releases chemicals called cannabinoids, which are only found in cannabis. One is called THC. THC causes the psychoactive effects of cannabis; in other words, THC causes the "high" from smoking cannabis. Pure THC oil is now available for purchase and can also be vaporized for inhalation directly into the lungs. This is very much like an e-cigarette- except THC replaces nicotine. Cannabinoids are believed to be why cannabis has therapeutic properties for many diseases- including autoimmune and chronic inflammatory conditions (asthma), pain and lung infections. These chemicals may work by affecting how the immune system functions. For example, THC and CBD can cause an immune cell in the body- called a T cell- to switch its armour. THC and CBD make a T cell become regulatory (as in regulates the disease to help make it better) and not pathogenic (disease-causing). In this research project, we will test whether cannabis alters the immune response to protect against infection. We will also provide answers as to whether there are long term health consequences of inhaling cannabis on a regular basis. Given the paucity of information on the long term consequences of cannabis smoke, together with the increasing use of pure cannabinoids for medical purposes, we are in a unique position to provide novel mechanistic evidence on the health impact of cannabis.