Grant: CIHR Fellowship

Heart diseases are the leading cause of death in the world. These deaths are often caused by acute blockage of blood flow to the heart or brain. The most common reason for the blockage is narrowing of blood vessels that supply blood to the heart or brain. This is a result of the accreting fatty deposits on the inner walls of blood vessels. Currently, scientists think these fatty deposits are caused by white blood cells eating too many lipids. This is because lipid carriers in the bloodstream can be modified and will accumulate on the vessel wall over time. White blood cells are attracted to these lipid carriers and will attempt to clear them. Scientists have a good understanding on how a white blood cell clears a single lipid carrier. White blood cells will take in these single lipid carriers and send them to specialized compartments within the cells called "lysosomes". Lysosome to cells is like stomach to animals because they contain acidic environment that helps digest the internalized materials. This is like how food is digested in the stomach. However, most lipid carriers found in the fatty deposits form large clumps and are stuck to the vessel wall. Thus, it is impossible for white blood cells to clear them in the same way as they would clear single lipid carriers. Our lab has discovered that white blood cells use a different approach to clear these large clumps of lipid carriers. Instead of internalizing them and send them to lysosomes, white blood cells will surround them and send their lysosomes out. This allows white blood cells to form a stomach-like compartment outside of the cell that can help digest these large clumps of lipid carriers. However, the detail of this disease-causing process is still poorly understood. The goal of my research is to further outline the basic biology behind this disease-causing process. Based on this new information, it is hoped that scientists can develop new treatments to help prevent heart diseases.