Library Subscription: Guest
Begell Digital Portal Begell Digital Library eBooks Journals References & Proceedings Research Collections
Critical Reviews™ in Immunology
IF: 1.404 5-Year IF: 3.347 SJR: 0.706 SNIP: 0.55 CiteScore™: 2.19

ISSN Print: 1040-8401
ISSN Online: 2162-6472

Volume 40, 2020 Volume 39, 2019 Volume 38, 2018 Volume 37, 2017 Volume 36, 2016 Volume 35, 2015 Volume 34, 2014 Volume 33, 2013 Volume 32, 2012 Volume 31, 2011 Volume 30, 2010 Volume 29, 2009 Volume 28, 2008 Volume 27, 2007 Volume 26, 2006 Volume 25, 2005 Volume 24, 2004 Volume 23, 2003 Volume 22, 2002 Volume 21, 2001 Volume 20, 2000 Volume 19, 1999 Volume 18, 1998 Volume 17, 1997 Volume 16, 1996 Volume 15, 1995 Volume 14, 1994

Critical Reviews™ in Immunology

DOI: 10.1615/CritRevImmunol.v32.i6.10
pages 463-488

M1 and M2 Macrophages: Oracles of Health and Disease

Charles Mills
Biomedical Consultants, 16930 197th St. N, Marine, MN, 55047


The purpose of immunology is simple. Cure or prevent disease. M1/M2 is useful because it is simple. M1/M2 describes the two major and opposing activities of macrophages. M1 activity inhibits cell proliferation and causes tissue damage while M2 activity promotes cell proliferation and tissue repair. Remarkably, the molecules primarily responsible for these "Fight" (NO) or "Fix" (Ornithine) activities both arise from arginine, and via enzymatic pathways (iNOS and arginase) that down regulate each other. The names M1 and M2 were chosen because M1 and M2 macrophages promote Th1 and Th2 responses, respectively. Products of Th1 and Th2 responses (e.g., IFN-γ, IL-4) also down regulate M2 and M1activity, respectively. Thus, M1/M2 demonstrated the importance of Innate Immunity and how it is linked to Adaptive Immunity in a beautifully counterbalanced system. "Civilization" and increased longevity present new disease challenges such as cancer and atherosclerosis that do not display classical "foreign" antigens. And, these diseases are often associated with (or caused by) M1- or M2- type responses that were formerly useful for fighting infections, but now are inappropriate in our increasingly "germ-free" societies. In turn, there is considerable potential for modulating M1 or M2 Innate responses in modern diseases to achieve better health. Finally, since M1 and Th1 (or M2 and Th2) often work in concert to produce characteristic immune responses and disease pathologies, it is recommended that Immune Type 1 or 2 (IT1, IT2) would be a simpler and unifying terminology going forward.

Articles with similar content:

Understanding How Lipopolysaccharide Impacts CD4 T-Cell Immunity
Critical Reviews™ in Immunology, Vol.28, 2008, issue 4
Anthony T. Vella, Jeremy P. McAleer
Dendritic Cell Tumor Killing Activity and Its Potential Applications in Cancer Immunotherapy
Critical Reviews™ in Immunology, Vol.33, 2013, issue 1
Neale Hanke, Darya Alizadeh, Nicolas Larmonier, Emmanuel Katsanis
The Human Immune System against Staphylococcus epidermidis
Critical Reviews™ in Immunology, Vol.39, 2019, issue 3
Mirzaei Rasoul, Mohammadzadeh Rokhsareh, Shokri Moghadam Mohammad, Moradi Ahmadreza, Karampoor Sajad
Human T-Cell Development and Thymic Egress: An Infectious Disease Perspective
Forum on Immunopathological Diseases and Therapeutics, Vol.6, 2015, issue 1-2
Christel H. Uittenbogaart, Rachel S. Resop
Exosome Release by Primary B Cells
Critical Reviews™ in Immunology, Vol.29, 2009, issue 3
Alexander McLellan