Professor Michael Hickey says leukocytes, or white blood cells, are both the good and bad guys of our immune system. While these cells are critical to our ability to fight infections and heal our tissues after injury, they are also responsible for some of the most debilitating inflammatory diseases, including rheumatoid arthritis, asthma, multiple sclerosis and inflammatory kidney disease. Michael’s laboratory investigates the behaviour of leukocytes in inflamed tissues and the blood vessels that supply them, using highly advanced microscopes to visualise white blood cells in tissues. The overall approach of the laboratory stems from the idea that only by directly visualising white blood cells in action can we aim to understand how they contribute to inflammatory diseases, and thereby identify new ways to tackle these conditions.