Immunology Select

The inflammatory response—characterized by release of cytokines such as TNFα and IL-1β and infiltration of infected or injured tissue by macrophages and neutrophils—is the first line of defense against infection by pathogens. Although an early inflammatory response is beneficial in stemming the tide of infection, a prolonged response may result in severe illness or even death. For example, the 1918 Spanish influenza virus was lethal because it triggered a “cytokine storm” that resulted in severe lung damage. An inappropriate and prolonged inflammatory response to normal nonpathogenic gut bacteria is a cause of Crohn's disease. Meanwhile, insidious low-level inflammation in the tumor microenvironment aids and abets tumor cells in their quest to become metastatic. Understanding the triggers of inflammation and the signaling pathways involved in cytokine production and immune cell mobilization will be essential for developing therapeutics to treat diseases caused by a runaway inflammatory response