Grant: Project Grant

Around the world there are an estimated 200 million cannabis users with the majority of these individuals deciding to smoke. Canada is the first G8 country to legalize recreational cannabis use, with an estimated 20% of the population having smoked cannabis in the last year. Smoking cannabis results in a "high" due to effects on the brain. Unfortunately, smoking cannabis can result in bronchitis, a swelling and inflammation of the breathing tubes in the lung. The breathing tubes are lined with cells called "epithelial cells" and other immune cells that help fight infections. The negative impact of tobacco smoke on epithelial cells and immune cells is well known, but whether or not cannabis smoke does the same things remains unknown. We seek to determine the impact of smoke exposures from different strains of cannabis on human lung immune defences against viruses. Our project will use human lung epithelial cells and immune cells from volunteer donors. We will grow these cells in plastic dishes that mimic the human lung environment. Using these human lung models, we will examine how exposure to increasing amounts of cannabis smoke impacts the ability of the cells to survive defend the lung against viruses. To understand how cannabis works in a living organism, we will perform cannabis smoke exposures to mice following by exposing the animals to virus that cause lung illnesses. Lastly, we will follow a group of human subjects that are cannabis smokers and individuals that do not smoke for a period of 24-months, documenting the number of lung illnesses and their perceived lung health. Collectively, our proposed studies will form a foundation for understanding the impact of cannabis smoke exposure on lung immune function in the context of clinically relevant viral exposures, guiding responsible use of cannabis by the population, regulation by government authorities, and production practices by commercial entities.