Hypoalphalipoproteinemia and BRAF(V600E) Mutation Are Major Predictors of Aortic Infiltration in the Erdheim-Chester Disease

作者：Cohen Aubart Fleur; Guerin Maryse; Poupel Lucie; Cluzel Philippe; Saint Charles Flora; Charlotte Frederic; Arsafi Youssef; Emile Jean Francois; Frisdal Eric; Le Goff Carine^*; Donadieu Jean; Amoura Zahir; Lesnik Philippe; Haroche Julien^*; Le Goff Wilfried^*

来源：Arteriosclerosis, Thrombosis, and Vascular Biology, 2018, 38(8): 1913-1925.

DOI：10.1161/ATVBAHA.118.310803

• ATP-binding cassette A1
• cardiovascular diseases
• Erdheim-Chester Disease
• histiocyte
• hypoalphalipoproteinemia
• macrophage

Objective Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis characterized by the infiltration of multiple tissues with lipid-laden histiocytes. Cardiovascular involvement is frequent in ECD and leads to a severe prognosis. The objective of this study was to determine whether an alteration of lipid metabolism participates in the lipid accumulation in histiocytes and the cardiovascular involvement in ECD.
Approach and Results An analysis of plasma lipid levels indicated that male ECD patients carrying the BRAF(V600E) (B-Raf proto-oncogene, serine/threonine kinase) mutation exhibited hypoalphalipoproteinemia, as demonstrated by low plasma HDL-C (high-density lipoprotein cholesterol) levels. Capacity of sera from male BRAF(V600E) ECD patients to mediate free cholesterol efflux from human macrophages was reduced compared with control individuals. Cardiovascular involvement was detected in 84% of the ECD patients, and we reported that the presence of the BRAF(V600E) mutation and hypoalphalipoproteinemia is an independent determinant of aortic infiltration in ECD. Phenotyping of blood CD14(+) cells, the precursors of histiocytes, enabled the identification of a specific inflammatory signature associated with aortic infiltration which was partially affected by the HDL phenotype. Finally, the treatment with vemurafenib, an inhibitor of the BRAF(V600E) mutation, restored the defective sera cholesterol efflux capacity and reduced the aortic infiltration.
Conclusions Our findings indicate that hypoalphalipoproteinemia in male ECD patients carrying the BRAF(V600E) mutation favors the formation of lipid-laden histiocytes. In addition, we identified the BRAF status and the HDL phenotype as independent determinants of the aortic involvement in ECD with a potential role of HDL in modulating the infiltration of blood CD14(+) cells into the aorta.

• 出版日期2018-8