MicroRNA-155 promotes atherosclerosis by repressing Bcl6 in macrophages

Maliheh Nazari-Jahantigh, Yuanyuan Wei, Heidi Noels, Shamima Akhtar, Zhe Zhou, Rory R. Koenen, Kathrin Heyll, Felix Gremse, Fabian Kiessling, Jochen Grommes, Christian Weber, Andreas Schober*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

385 Citations (Web of Science)


Macrophages in atherosclerotic plaques drive inflammatory responses, degrade lipoproteins, and phagocytose dead cells. MicroRNAs (miRs) control the differentiation and activity of macrophages by regulating the signaling of key transcription factors. However, the functional role of macrophage-related miRs in the immune response during atherogenesis is unknown. Here, we report that miR-155 is specifically expressed in atherosclerotic plaques and proinflammatory macrophages, where it was induced by treatment with mildly oxidized LDL (moxLDL) and IFN-gamma. Leukocyte-specific Mir155 deficiency reduced plaque size and number of lesional macrophages after partial carotid ligation in atherosclerotic (Apoe(-/-)) mice. In macrophages stimulated with moxLDL/IFN-gamma in vitro, and in lesional macrophages, loss of Mir155 reduced the expression of the chemokine CCL2, which promotes the recruitment of monocytes to atherosclerotic plaques. Additionally, we found that miR-155 directly repressed expression of BCL6, a transcription factor that attenuates proinflammatory NE-kappa B signaling. Silencing of Bcl6 in mice harboring Mir155(-/-) macrophages enhanced plaque formation and CCL2 expression. Taken together, these data demonstrated that miR-155 plays a key role in atherogenic programming of macrophages to sustain and enhance vascular inflammation.
Original languageEnglish
Pages (from-to)4190-4202
JournalJournal of Clinical Investigation
Issue number11
Publication statusPublished - Nov 2012

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