REVIEW: Functional Phenotypes of Macrophages and the M1–M2 Polarization Concept. Part I. Proinflammatory Phenotype

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Y. Sh. Schwartz^1* and A. V. Svistelnik²

¹Research Institute of Internal Medicine, Siberian Branch of the Russian Academy of Medical Sciences, ul. B. Bogatkova 175/1, 630089 Novosibirsk, Russia; fax: (383) 264-2516; E-mail: YShSchwartz@mail.ru

²Meshalkin Research Institute for Circulation Pathology, ul. Rechkunovskaya 15, 630055 Novosibirsk, Russia; fax: (383) 332-4244; E-mail: mail@meshalkin.ru

^* To whom correspondence should be addressed.

Received November 21, 2011

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Current concepts concerning the main functional phenotypes of mononuclear phagocytes are systematized, molecular mechanisms of their formation are considered, and the functional polarization concept of macrophages is critically analyzed. Mechanisms of macrophage priming activation mediated by pattern recognition receptors TLR, NLR, RLR, and CLR are described, and the features of each phenotype acquired via various pattern recognition receptors are emphasized. It is concluded that there is a huge variety of proinflammatory phenotypes from highly to poorly polarized ones. Thus the widespread notion of “classical activation” of macrophage concerns just a particular case of proinflammatory phenotype formation.

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KEY WORDS: macrophage, polarization, phenotype, TLR, NLR, RLR, CLR

DOI: 10.1134/S0006297912030030

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