First Author | Jiménez-Garcia L | Year | 2015 |
Journal | Eur J Immunol | Volume | 45 |
Issue | 1 | Pages | 273-86 |
PubMed ID | 25328047 | Mgi Jnum | J:222320 |
Mgi Id | MGI:5644361 | Doi | 10.1002/eji.201444806 |
Citation | Jimenez-Garcia L, et al. (2015) Critical role of p38 MAPK in IL-4-induced alternative activation of peritoneal macrophages. Eur J Immunol 45(1):273-86 |
abstractText | Alternative activation of macrophages plays an important role in a range of physiological and pathological processes. This alternative phenotype, also known as M2 macrophages, is induced by type 2 cytokines such as IL-4. The binding of IL-4 to its receptor leads to activation of two major signaling pathways: STAT-6 and PI3K. However, recent studies have described that p38 MAPK might play a role in IL-4-dependent signaling in some cells, although its role in macrophages is still controversial. In this study, we investigated whether p38 MAPK plays a role in the polarization of macrophages in mice. Our results reveal that IL-4 induces phosphorylation of p38 MAPK in thioglycollate-elicited murine peritoneal macrophages, in addition to STAT-6 and PI3K activation. Furthermore, p38 MAPK inactivation, by gene silencing or pharmacological inhibition, suppressed IL-4-induced typical M2 markers, indicating the involvement of p38 MAPK in the signaling of IL-4 leading to M2-macrophage polarization. Moreover, p38 MAPK inhibition blocked phosphorylation of STAT-6 and Akt, suggesting that p38 MAPK is upstream of these signaling pathways. Finally, we show that in an in vivo model of chitin-induced M2 polarization, p38 MAPK inhibition also diminished activation of M2 markers. Taken together, our data establish a new role for p38 MAPK during IL-4-induced alternative activation of macrophages. |