Chronic inflammation is responsible for many of the debilitating effects of auto-immune, and other, diseases. In pathogenic inflammatory diseases, high levels of immune system cells (particularly macrophages, neutrophils, and TH1 cells) migrate from the blood to the tissue over a prolonged period of time. Pretend that you are writing a review article about this. Explain the process of chronic inflammation, how immune cells leave the circulatory system and how directed/stop at the correct location?