This article was originally posted on RealClearScience.

Immunologists are fond of making analogies with law enforcement to explain how the immune system works. Macrophages, cells which gobble up invading microbes, are often compared to beat cops, patrolling the neighborhood for any signs of trouble. Neutrophils, which my former graduate school advisor likens to “little hand grenades,” are like miniature SWAT teams, rushing in with guns blazing, shooting first and asking questions later. T-cells, which coordinate the immune response, are akin to intelligence officers, while the antibody-producing B-cells, which target highly-wanted suspect pathogens, are similar to the FBI. Continue reading →