Hematopoietic ChemR23 (Chemerin Receptor 23) Fuels Atherosclerosis by Sustaining an M1 Macrophage-Phenotype and Guidance of Plasmacytoid Dendritic Cells to Murine Lesions-Brief Report.

Objective- Expression of the chemokine-like receptor ChemR23 (chemerin receptor 23) has been specifically attributed to plasmacytoid dendritic cells (pDCs) and macrophages and ChemR23 has been suggested to mediate an inflammatory immune response in these cells. Because chemokine receptors are important in perpetuating chronic inflammation, we aimed to establish the role of ChemR23-deficiency on macrophages and pDCs in atherosclerosis. Approach and Results- ChemR23-knockout/knockin mice expressing eGFP (enhanced green fluorescent protein) were generated and after crossing with apolipoprotein E-deficient ( Apoe-/- ChemR23 e/e) animals were fed a western-type diet for 4 and 12 weeks. Apoe-/- ChemR23 e/e mice displayed reduced lesion formation and reduced leukocyte adhesion to the vessel wall after 4 weeks, as well as diminished plaque growth, a decreased number of lesional macrophages with an increased proportion of M2 cells and a less inflammatory lesion composition after 12 weeks of western-type diet feeding. Hematopoietic ChemR23-deficiency similarly reduced atherosclerosis. Additional experiments revealed that ChemR23-deficiency induces an alternatively activated macrophage phenotype, an increased cholesterol efflux and a systemic reduction in pDC frequencies. Consequently, expression of the pDC marker SiglecH in atherosclerotic plaques of Apoe-/- ChemR23 e/e mice was declined. ChemR23-knockout pDCs also exhibited a reduced migratory capacity and decreased CCR (CC-type chemokine receptor)7 expression. Finally, adoptive transfer of sorted wild-type and knockout pDCs into Apoe-/- recipient mice revealed reduced accumulation of ChemR23-deficient pDCs in atherosclerotic lesions. Conclusions- Hematopoietic ChemR23-deficiency increases the proportion of alternatively activated M2 macrophages in atherosclerotic lesions and attenuates pDC homing to lymphatic organs and recruitment to atherosclerotic lesions, which synergistically restricts atherosclerotic plaque formation and progression.

Vascular CXCR4 Limits Atherosclerosis by Maintaining Arterial Integrity: Evidence From Mouse and Human Studies.

BACKGROUND: The CXCL12/CXCR4 chemokine ligand/receptor axis controls (progenitor) cell homeostasis and trafficking. So far, an atheroprotective role of CXCL12/CXCR4 has only been implied through pharmacological intervention, in particular, because the somatic deletion of the CXCR4 gene in mice is embryonically lethal. Moreover, cell-specific effects of CXCR4 in the arterial wall and underlying mechanisms remain elusive, prompting us to investigate the relevance of CXCR4 in vascular cell types for atheroprotection. METHODS: We examined the role of vascular CXCR4 in atherosclerosis and plaque composition by inducing an endothelial cell (BmxCreERT2-driven)-specific or smooth muscle cell (SMC, SmmhcCreERT2- or TaglnCre-driven)-specific deficiency of CXCR4 in an apolipoprotein E-deficient mouse model. To identify underlying mechanisms for effects of CXCR4, we studied endothelial permeability, intravital leukocyte adhesion, involvement of the Akt/WNT/ß-catenin signaling pathway and relevant phosphatases in VE-cadherin expression and function, vascular tone in aortic rings, cholesterol efflux from macrophages, and expression of SMC phenotypic markers. Finally, we analyzed associations of common genetic variants at the CXCR4 locus with the risk for coronary heart disease, along with CXCR4 transcript expression in human atherosclerotic plaques. RESULTS: The cell-specific deletion of CXCR4 in arterial endothelial cells (n=12-15) or SMCs (n=13-24) markedly increased atherosclerotic lesion formation in hyperlipidemic mice. Endothelial barrier function was promoted by CXCL12/CXCR4, which triggered Akt/WNT/ß-catenin signaling to drive VE-cadherin expression and stabilized junctional VE-cadherin complexes through associated phosphatases. Conversely, endothelial CXCR4 deficiency caused arterial leakage and inflammatory leukocyte recruitment during atherogenesis. In arterial SMCs, CXCR4 sustained normal vascular reactivity and contractile responses, whereas CXCR4 deficiency favored a synthetic phenotype, the occurrence of macrophage-like SMCs in the lesions, and impaired cholesterol efflux. Regression analyses in humans (n=259 796) identified the C-allele at rs2322864 within the CXCR4 locus to be associated with increased risk for coronary heart disease. In line, C/C risk genotype carriers showed reduced CXCR4 expression in carotid artery plaques (n=188), which was furthermore associated with symptomatic disease. CONCLUSIONS: Our data clearly establish that vascular CXCR4 limits atherosclerosis by maintaining arterial integrity, preserving endothelial barrier function, and a normal contractile SMC phenotype. Enhancing these beneficial functions of arterial CXCR4 by selective modulators might open novel therapeutic options in atherosclerosis.

Human Neutrophil Peptide 1 Limits Hypercholesterolemia-induced Atherosclerosis by Increasing Hepatic LDL Clearance.

Increases in plasma LDL-cholesterol have unequivocally been established as a causal risk factor for atherosclerosis. Hence, strategies for lowering of LDL-cholesterol may have immediate therapeutic relevance. Here we study the role of human neutrophil peptide 1 (HNP1) in a mouse model of atherosclerosis and identify its potent atheroprotective effect both upon transgenic overexpression and therapeutic delivery. The effect was found to be due to a reduction of plasma LDL-cholesterol. Mechanistically, HNP1 binds to apolipoproteins enriched in LDL. This interaction facilitates clearance of LDL particles in the liver via LDL receptor. Thus, we here identify a non-redundant mechanism by which HNP1 allows for reduction of LDL-cholesterol, a process that may be therapeutically instructed to lower cardiovascular risk.

Interactions of Factors and Profiles of Incontinent Nursing Home Residents and Hospital Patients: A Classification Tree Analysis.

PURPOSE: To investigate the interactions among well-known influencing factors for urinary incontinence (UI), fecal incontinence (FI), and double urinary and fecal incontinence (DI) in the nursing home and hospital setting and to identify profiles of UI, FI, and DI residents and patients. SUBJECTS AND SETTING: Data from more than 4200 residents and patients from 16 nursing homes and 36 hospitals were collected. DESIGN: This was a cross-sectional study. METHODS: A cross-sectional study was used for data collection. The Austrian version of the International Prevalence Measurement of Care Problems survey was used to collect data about different nursing care problems (eg, pressure ulcer and incontinence). To improve objectivity, 2 nurses assessed each resident/patient. The Care Dependency Scale (CDS) was used to measure the degree of care dependency regarding different needs such as mobility, with lower scores indicating a higher level of care dependency. A classification and regression tree analysis was used to determine the interactions among factors and develop profiles of incontinent residents and patients. RESULTS: Interactions between the CDS-items of states of Dress/Undress, Hygiene, Mobility, and Eat/Drink and age based on incontinence were found in nursing home residents. In contrast, interactions between the CDS-items Hygiene and Eat/Drink, as well as age and gender based on incontinence, were identified in hospitalized patients. Residents with UI were care dependent with reference to the CDS-item Dress/Undress. Patients with UI were older than 77.5 years and completely, or to a great extent, care dependent with reference to the CDS-item Hygiene. Nursing home residents with DI were completely, or to a great extent, care dependent with regard to the CDS-item Hygiene and completely care dependent with reference to the CDS-item Dress/Undress. In comparison, hospitalized DI patients were completely, or to a great extent, care dependent with regard to the CDS-item Hygiene. CONCLUSIONS: The results of this study show that independently associated factors for incontinence also influence each other. Furthermore, these interactions increase the prevalence for incontinence and differ with regard to the type of incontinence and setting.

Involving the consumers: An exploration of users' and caregivers' needs and expectations on a fall prevention brochure: A qualitative study.

This study aims to explore and compare nursing home residents', family members', and nursing staff's needs and expectations regarding a fall prevention brochure. Focus groups were carried out with 25 residents, 12 family members and 14 nursing staff separately, from three randomly selected nursing homes. Qualitative content analysis was used to analyze the data using a concept-driven coding frame. Results showed that residents want to be informed about dealing with extrinsic fall risks and coping strategies after a fall event. In addition, family members wanted to have detailed information on intrinsic fall risks as well as specific fall prevention strategies, such as body exercises. Of special importance for nursing staff was that not all falls are preventable even when preventive measures were taken. As the need and expectations of users differ substantially, one brochure could not comprise all postulated criteria and different brochures are necessary for residents and for family members.

Evaluation of the BDCA2-DTR Transgenic Mouse Model in Chronic and Acute Inflammation.

BACKGROUND AND AIMS: Plasmacytoid dendritic cells (pDCs) are a small subset of dendritic cells and the main producers of type I interferons. Besides their contribution to tolerance, they are known to be involved in autoimmune diseases and have recently been implicated in atherosclerosis. However, their precise involvement, particularly in advanced lesion development, remains elusive. Hence, we investigated the role of pDCs in atherogenesis vs atheroprogression by specifically depleting this cell population using the BDCA2-DTR mouse model bred to Apolipoprotein E (Apoe-/-) deficient mice. METHODS AND RESULTS: Our results revealed that continuous diphtheria toxin-induced pDC depletion in Apoe-/- BDCA2-DTR mice receiving a high-fat diet (HFD) for 4 weeks did not alter lesion size or composition. Instead, these mice displayed increased B cell numbers and altered levels of inflammatory cytokines. Analysis of depletion efficiency showed that complete pDC depletion could only be sustained for one week and reoccurring pDCs sorted after 4 weeks did not express DTR anymore. Consequently, we analyzed lesion development in a model of partial carotid ligation, inducing established lesions after 5 weeks of HFD feeding, and only depleted pDCs during the last week of 5 weeks HFD feeding. Despite short-term, but efficient pDC depletion, we observed no differences in atherosclerotic lesion development, but changes in inflammatory cytokine titers. To assure the functionality of the BDCA2-DTR model in acute settings, we additionally examined the effect of pDC depletion in an indirect acute lung injury (iALI) model. This time, efficient pDC depletion resulted in a significantly reduced macrophage and neutrophil accumulation in the lung 12 hours after LPS challenge, underlining a pro-inflammatory role of pDCs in the innate immune response in iALI. CONCLUSION: Taken together, the BDCA2-DTR mouse model only allows efficient pDC depletion for one week, which subsequently restricts its usability to more acute but not chronic inflammatory disease models.

Incontinence care in nursing homes: a cross-sectional study.

AIMS: To describe the quality of incontinence care in nursing homes. Main outcome measures were: (1) availability of structural quality indicators on ward and institutional levels; (2) use of nursing interventions as quality indicators on a process level; (3) prevalence of incontinence as an outcome indicator. BACKGROUND: Incontinence in older people is a major problem in nursing care that presents a high workload for nurses, increases costs and places a high burden on affected individuals. The availability of structural indicators, and the use of nursing interventions, is recommended to improve the quality of care. Only limited amounts of reliable and valid data are available regarding the quality of incontinence care in nursing homes. DESIGN: A cross-sectional multicentre study in 16 nursing homes (N = 1302) in 2013. METHODS: A standardized and validated questionnaire was used for data collection. Each resident was assessed by two trained nurses. RESULTS/FINDINGS: The primary outcome of the study indicated that structural indicators, such as the availability of information brochures, are limited in nursing homes. On a process level, the provision of body worn pads or underlay pads to protect beds or chairs were most frequently used and training interventions were only delivered to a small proportion of residents with incontinence. The prevalence of all types of incontinence, particularly double incontinence, was high (69·2%). CONCLUSION: Due to the high prevalence of double incontinence and low rate of training interventions regarding this type of incontinence, ongoing efforts to improve the quality of incontinence care are warranted.

Characterization of the CD14++CD16+ monocyte population in human bone marrow.

Numerous studies have divided blood monocytes according to their expression of the surface markers CD14 and CD16 into following subsets: classical CD14(++)CD16(-), intermediate CD14(++)CD16(+) and nonclassical CD14(+)CD16(++) monocytes. These subsets differ in phenotype and function and are further correlated to cardiovascular disease, inflammation and cancer. However, the CD14/CD16 nature of resident monocytes in human bone marrow remains largely unknown. In the present study, we identified a major population of CD14(++)CD16(+) monocytes by using cryopreserved bone marrow mononuclear cells from healthy donors. These cells express essential monocyte-related antigens and chemokine receptors such as CD11a, CD18, CD44, HLA-DR, Ccr2, Ccr5, Cx3cr1, Cxcr2 and Cxcr4. Notably, the expression of Ccr2 was inducible during culture. Furthermore, sorted CD14(++)CD16(+) bone marrow cells show typical macrophage morphology, phagocytic activity, angiogenic features and generation of intracellular oxygen species. Side-by-side comparison of the chemokine receptor profile with unpaired blood samples also demonstrated that these rather premature medullar monocytes mainly match the phenotype of intermediate and partially of (non)classical monocytes. Together, human monocytes obviously acquire their definitive CD14/CD16 signature in the bloodstream and the medullar monocytes probably transform into CD14(++)CD16- and CD14(+)CD16(++) subsets which appear enriched in the periphery.

Deficiency of the sialyltransferase St3Gal4 reduces Ccl5-mediated myeloid cell recruitment and arrest: short communication.

RATIONALE: Sialylation by α2,3-sialyltransferases has been shown to be a crucial glycosylation step in the generation of functional selectin ligands. Recent evidence suggests that sialylation also affects the binding of chemokines to their corresponding receptor. OBJECTIVE: Because the chemokine receptors for Ccl5 and Ccl2 are important in atherogenic recruitment of neutrophils and monocytes, we here investigated the role of α2,3-sialyltransferase IV (ST3Gal-IV) in Ccl5- and Ccl2-mediated myeloid cell arrest and further studied its relevance in a mouse model of atherosclerosis. METHODS AND RESULTS: St3Gal4-deficient myeloid cells showed a reduced binding of Ccl5 and an impaired Ccl5-triggered integrin activation. Correspondingly, Ccl5-induced arrest on tumor necrosis factor-α-stimulated endothelium was almost completely abrogated, as observed in flow chamber adhesion assays and during ex vivo perfusion or intravital microscopy of carotid arteries. Moreover, Ccl5-triggered neutrophil and monocyte extravasation into the peritoneal cavity was severely reduced in St3Gal4(-/-) mice. In contrast, St3Gal4 deficiency did not significantly affect Ccl2 binding and only marginally decreased Ccl2-induced flow arrest of myeloid cells. In agreement with the crucial role of leukocyte accumulation in atherogenesis, and the importance of Ccl5 chemokine receptors mediating myeloid cell recruitment to atherosclerotic vessels, St3Gal4 deficiency drastically reduced the size, stage, and inflammatory cell content of atherosclerotic lesions in Apoe(-/-) mice on high-fat diet. CONCLUSIONS: In summary, these findings identify ST3Gal-IV as a promising target to reduce inflammatory leukocyte recruitment and arrest.

Distinct functions of chemokine receptor axes in the atherogenic mobilization and recruitment of classical monocytes.

We used a novel approach of cytostatically induced leucocyte depletion and subsequent reconstitution with leucocytes deprived of classical (inflammatory/Gr1(hi) ) or non-classical (resident/Gr1(lo) ) monocytes to dissect their differential role in atheroprogression under high-fat diet (HFD). Apolipoprotein E-deficient (Apoe(-/-) ) mice lacking classical but not non-classical monocytes displayed reduced lesion size and macrophage and apoptotic cell content. Conversely, HFD induced a selective expansion of classical monocytes in blood and bone marrow. Increased CXCL1 levels accompanied by higher expression of its receptor CXCR2 on classical monocytes and inhibition of monocytosis by CXCL1-neutralization indicated a preferential role for the CXCL1/CXCR2 axis in mobilizing classical monocytes during hypercholesterolemia. Studies correlating circulating and lesional classical monocytes in gene-deficient Apoe(-/-) mice, adoptive transfer of gene-deficient cells and pharmacological modulation during intravital microscopy of the carotid artery revealed a crucial function of CCR1 and CCR5 but not CCR2 or CX3 CR1 in classical monocyte recruitment to atherosclerotic vessels. Collectively, these data establish the impact of classical monocytes on atheroprogression, identify a sequential role of CXCL1 in their mobilization and CCR1/CCR5 in their recruitment.