The Origin of a Paradigm

In this issue of the Journal of Innate Immunity , we are privileged to publish an article by Siamon Gordon [1] , Professor Emeritus of Cellular Pathology at the University of Oxford, commemorating the life and achievements of Elie Metchnikoff (1845–1916). Siamon Gordon is an outstanding scientist in the field of macrophage research and has made many important discoveries, e.g. the pattern recognition receptor dectin-1 [2] . Elie Metchnikoff and Paul Ehrlich shared the Nobel Prize in Physiology or Medicine in 1908 and both may be considered the founders of innate immunity, even if Charles Janeway was the one who conceptualized this entity of host defense many years later. The groundbreaking discovery of phagocytosis in 1882 and the personal life of Elie Metchnikoff continue to fascinate [3] . From an earlier rather simplistic view of macrophages, this area has expanded rapidly in recent years, to now include a large number of complex phenotypes [4] . In addition, important roles in a broad range of disease conditions, such as atherosclerosis, sepsis, bacterial infection, allergic inflammation, autophagy and viral infections, have been established [5–13] . Further emphasizing their importance, macrophages and cells with macrophage-like properties occurred early during evolution [14, 15] . In a research context that is becoming increasingly complex, a holistic view on macrophages is helpful. A very interesting review on M1 and M2 macrophages by Charles D. Mills and Klaus Ley [16] was recently published in this journal. ‘Inhibit’ type macrophages (called M1) can rapidly kill pathogens, and are thus part of the primary host defense while ‘Heal’ type macrophages (M2) routinely repair and maintain tissue integrity. The increasing number of observed anomalies that accumulate can be the origin of new paradigms. Heiko Herwald , Lund Arne Egesten , Lund Published online: April 28, 2016 Journal of Innate Immunity