Emerging role of micro<scp>RNA</scp>s in regulating macrophage activation and polarization in immune response and inflammation

<jats:title>Summary</jats:title><jats:p>Diversity and plasticity are hallmarks of macrophages. Classically activated macrophages are considered to promote T helper type 1 responses and have strong microbicidal, pro‐inflammatory activity, whereas alternatively activated macrophages are supposed to be associated with promotion of tissue remodelling and responses to anti‐inflammatory reactions. Transformation of different macrophage phenotypes is reflected in their different, sometimes even opposite, roles in various diseases or inflammatory conditions. Micro<jats:styled-content style="fixed-case">RNA</jats:styled-content>s (mi<jats:styled-content style="fixed-case">RNA</jats:styled-content>s) have emerged as critical regulators of macrophage polarization (<jats:styled-content style="fixed-case">MP</jats:styled-content>). Several mi<jats:styled-content style="fixed-case">RNA</jats:styled-content>s are induced by Toll‐like receptors signalling in macrophages and target the 3′‐untranslated regions of <jats:styled-content style="fixed-case">mRNA</jats:styled-content>s encoding key molecules involved in <jats:styled-content style="fixed-case">MP</jats:styled-content>. Therefore, identification of mi<jats:styled-content style="fixed-case">RNA</jats:styled-content>s related to the dynamic changes of <jats:styled-content style="fixed-case">MP</jats:styled-content> and understanding their functions in regulating this process are important for discussing the molecular basis of disease progression and developing novel mi<jats:styled-content style="fixed-case">RNA</jats:styled-content>‐targeted therapeutic strategies. Here, we review the current knowledge of the role of mi<jats:styled-content style="fixed-case">RNA</jats:styled-content>s in <jats:styled-content style="fixed-case">MP</jats:styled-content> with relevance to immune response and inflammation.</jats:p>