TY - JOUR
T1 - miR-33 Silencing Reprograms the Immune Cell Landscape in Atherosclerotic Plaques
AU - Afonso, Milessa Silva
AU - Sharma, Monika
AU - Schlegel, Martin
AU - Van Solingen, Coen
AU - Koelwyn, Graeme J.
AU - Shanley, Lianne C.
AU - Beckett, Lauren
AU - Peled, Daniel
AU - Rahman, Karishma
AU - Giannarelli, Chiara
AU - Li, Huilin
AU - Brown, Emily J.
AU - Khodadadi-Jamayran, Alireza
AU - Fisher, Edward A.
AU - Moore, Kathryn J.
N1 - Publisher Copyright:
© 2020 American Heart Association, Inc.
PY - 2021/4/16
Y1 - 2021/4/16
N2 - Rationale: MicroRNA-33 (miR-33 [post-transcriptionally in the rationale]) post-transcriptionally represses genes involved in lipid metabolism and energy homeostasis. Targeted inhibition of miR-33 increases plasma HDL (high-density lipoprotein) cholesterol and promotes atherosclerosis regression, in part, by enhancing reverse cholesterol transport and dampening plaque inflammation. However, how miR-33 reshapes the immune microenvironment of plaques remains poorly understood. Objective: To define how miR-33 inhibition alters the dynamic balance and transcriptional landscape of immune cells in atherosclerotic plaques. Methods and Results: We used single-cell RNA-sequencing of aortic CD45+ cells, combined with immunohistologic, morphometric, and flow cytometric analyses to define the changes in plaque immune cell composition, gene expression, and function following miR-33 inhibition. We report that anti-miR-33 treatment of Ldlr-/- mice with advanced atherosclerosis reduced plaque burden and altered the plaque immune cell landscape by shifting the balance of proatherosclerotic and antiatherosclerotic macrophage and T-cell subsets. By quantifying the kinetic processes that determine plaque macrophage burden, we found that anti-miR-33 reduced levels of circulating monocytes and splenic myeloid progenitors, decreased macrophage proliferation and retention, and promoted macrophage attrition by apoptosis and efferocytotic clearance. Single-cell RNA-sequencing of aortic arch plaques showed that anti-miR-33 reduced the frequency of MHCIIhi (major histocompatibility complex II) inflammatory and Trem2hi (Triggering Receptor Expressed On Myeloid Cells 2) metabolic macrophages, but not tissue-resident macrophages. Furthermore, anti-miR-33 led to derepression of distinct miR-33 target genes in the different macrophage subsets: in resident and Trem2hi macrophages, anti-miR-33 relieved repression of miR-33 target genes involved in lipid metabolism (eg, Abca1, Ncoa1, Ncoa2, Crot), whereas in MHCIIhi macrophages, anti-miR-33 upregulated target genes involved in chromatin remodeling and transcriptional regulation. Anti-miR-33 also reduced the accumulation of aortic CD8+ T cells and CD4+ T-helper 1 cells, and increased levels of FoxP3+ (Forkhead Box P3) regulatory T cells in plaques, consistent with an immune-dampening effect on plaque inflammation. Conclusions: Our results provide insight into the immune mechanisms and cellular players that execute anti-miR-33's atheroprotective actions in the plaque.
AB - Rationale: MicroRNA-33 (miR-33 [post-transcriptionally in the rationale]) post-transcriptionally represses genes involved in lipid metabolism and energy homeostasis. Targeted inhibition of miR-33 increases plasma HDL (high-density lipoprotein) cholesterol and promotes atherosclerosis regression, in part, by enhancing reverse cholesterol transport and dampening plaque inflammation. However, how miR-33 reshapes the immune microenvironment of plaques remains poorly understood. Objective: To define how miR-33 inhibition alters the dynamic balance and transcriptional landscape of immune cells in atherosclerotic plaques. Methods and Results: We used single-cell RNA-sequencing of aortic CD45+ cells, combined with immunohistologic, morphometric, and flow cytometric analyses to define the changes in plaque immune cell composition, gene expression, and function following miR-33 inhibition. We report that anti-miR-33 treatment of Ldlr-/- mice with advanced atherosclerosis reduced plaque burden and altered the plaque immune cell landscape by shifting the balance of proatherosclerotic and antiatherosclerotic macrophage and T-cell subsets. By quantifying the kinetic processes that determine plaque macrophage burden, we found that anti-miR-33 reduced levels of circulating monocytes and splenic myeloid progenitors, decreased macrophage proliferation and retention, and promoted macrophage attrition by apoptosis and efferocytotic clearance. Single-cell RNA-sequencing of aortic arch plaques showed that anti-miR-33 reduced the frequency of MHCIIhi (major histocompatibility complex II) inflammatory and Trem2hi (Triggering Receptor Expressed On Myeloid Cells 2) metabolic macrophages, but not tissue-resident macrophages. Furthermore, anti-miR-33 led to derepression of distinct miR-33 target genes in the different macrophage subsets: in resident and Trem2hi macrophages, anti-miR-33 relieved repression of miR-33 target genes involved in lipid metabolism (eg, Abca1, Ncoa1, Ncoa2, Crot), whereas in MHCIIhi macrophages, anti-miR-33 upregulated target genes involved in chromatin remodeling and transcriptional regulation. Anti-miR-33 also reduced the accumulation of aortic CD8+ T cells and CD4+ T-helper 1 cells, and increased levels of FoxP3+ (Forkhead Box P3) regulatory T cells in plaques, consistent with an immune-dampening effect on plaque inflammation. Conclusions: Our results provide insight into the immune mechanisms and cellular players that execute anti-miR-33's atheroprotective actions in the plaque.
KW - adaptive immunity
KW - atherosclerosis
KW - inflammation
KW - macrophages
KW - microRNA
UR - http://www.scopus.com/inward/record.url?scp=85104427479&partnerID=8YFLogxK
U2 - 10.1161/CIRCRESAHA.120.317914
DO - 10.1161/CIRCRESAHA.120.317914
M3 - Article
C2 - 33593073
AN - SCOPUS:85104427479
SN - 0009-7330
VL - 128
SP - 1122
EP - 1138
JO - Circulation Research
JF - Circulation Research
IS - 8
ER -