Transcriptome Analysis Reveals Nonfoamy Rather Than Foamy Plaque Macrophages Are Proinflammatory in Atherosclerotic Murine Models.

RATIONALE: Monocyte infiltration into the subintimal space and its intracellular lipid accumulation are the most prominent features of atherosclerosis. To understand the pathophysiology of atherosclerotic disease, we need to understand the characteristics of lipid-laden foamy macrophages in the subintimal space during atherosclerosis. OBJECTIVE: We sought to examine the transcriptomic profiles of foamy and nonfoamy macrophages isolated from atherosclerotic intima. METHODS AND RESULTS: Single-cell RNA sequencing analysis of CD45+ leukocytes from murine atherosclerotic aorta revealed that there are macrophage subpopulations with distinct differentially expressed genes involved in various functional pathways. To specifically characterize the intimal foamy macrophages of plaque, we developed a lipid staining-based flow cytometric method for analyzing the lipid-laden foam cells of atherosclerotic aortas. We used the fluorescent lipid probe BODIPY493/503 and assessed side-scattered light as an indication of cellular granularity. BODIPYhiSSChi foamy macrophages were found residing in intima and expressing CD11c. Foamy macrophage accumulation determined by flow cytometry was positively correlated with the severity of atherosclerosis. Bulk RNA sequencing analysis showed that compared with nonfoamy macrophages, foamy macrophages expressed few inflammatory genes but many lipid-processing genes. Intimal nonfoamy macrophages formed the major population expressing IL (interleukin)-1ß and many other inflammatory transcripts in atherosclerotic aorta. CONCLUSIONS: RNA sequencing analysis of intimal macrophages from atherosclerotic aorta revealed that lipid-loaded plaque macrophages are not likely the plaque macrophages that drive lesional inflammation.

Local Immune Responses in Children and Adults with Allergic and Nonallergic Rhinitis.

BACKGROUND: Allergic rhinitis (AR) is the most common allergic disease but little is known about the difference of local immune responses in children and adults with AR. OBJECTIVE: To compare local immune responses between children and adults with AR and nonallergic rhinitis (NAR), and to investigate whether the association of local and systemic immune responses is different between the two age groups. METHODS: Fifty-one patients with chronic rhinitis were enrolled and grouped into children (N = 27, mean age 7.2 years) and adults (N = 24, mean age 29.9 years). Diagnosis of AR was based on symptoms, skin prick tests and serum specific IgEs. Nasal lavage (NAL) fluids were collected from all subjects and used to measure the levels of total IgE, specific IgEs to house dust mites (Dp and Df), and cytokines (TNF-α, IL-4, IL-10, IL-17A and IFN-γ). Flow cytometry was used to measure inflammatory cell types in NAL fluids. RESULTS: AR had significantly increased local levels of total IgE and specific IgEs to Dp and Df compared with NAR in both age groups (P < 0.05). Nasal eosinophils % (P = 0.01) was significantly increased only in children with AR. Local-systemic correlations of total IgE (r = 0.662, P = 0.000) and eosinophil % (r = 0.461, P = 0.015) between the peripheral blood and NAL fluids were found only in children. Moreover, children had correlations between total IgE and eosinophil % in the peripheral blood (r = 0.629, P = 0.001) and in NAL fluids (r = 0.373, P = 0.061). CONCLUSION: Elevated local IgE is a common feature of AR in children and adults. Local measures in NAR showed naïve state of immune response which disagree with the hypothesis of local allergic rhinitis. Children showed intense local inflammation and close local-systemic interactions compared to adults supporting pediatric AR as a distinct feature.

High cholesterol diet induces IL-1ß expression in adult but not larval zebrafish.

Recently, it has been demonstrated that high cholesterol diet induced hypercholesterolemia and vascular lipid oxidation and accumulation in zebrafish larvae, suggesting that zebrafish is a new promising atherosclerosis model in addition to mouse models. However, up to date, there was no report regarding inflammatory cytokine expression during the lipid accumulation in zebrafish larva and adult fish. In this study, we first demonstrated the expression levels of IL-1ß and TNF-α in high cholesterol diet (HCD)-fed zebrafish larvae, and found that although HCD induced vascular lipid accumulation, the cytokine expressions in the larvae were not changed by HCD. Furthermore, there was no significant difference in leukocyte accumulation in vessels between control and HCD fed group. But prolonged HCD induced IL-1ß expression in spleen and liver compared to those of control zebrafish, and produced very early stage of fatty streak lesion in dorsal aorta of 19 week HCD-fed zebrafish. These results indicate that HCD induced hypercholesterolemia and atherosclerotic changes in zebrafish are very early stage, and suggest the necessity of the generation of mutant zebrafish having a disruption in a lipid metabolism-related gene leading to severe hypercholesterolemia and advanced atherosclerosis.