The BioMimics 3D Helical Centreline Nitinol Stent in Chronic Limb Threatening Ischaemia and Complex Lesions: Three Year Outcomes of the MIMICS-3D Registry.

OBJECTIVE: There is a need for improved outcomes in the endovascular treatment of patients suffering from chronic limb threatening ischaemia (CLTI), highly calcified lesions, and chronic total occlusions (CTOs). The helical centreline self expanding BioMimics 3D stent might be particularly useful in these high risk subsets, combining flexibility and fracture resistance with radial strength. Herein, the performance of the BioMimics 3D stent was assessed in these high risk subsets. METHODS: MIMICS-3D is a prospective, multicentre, European real world registry. This was a post hoc analysis, comparing patients with CLTI vs. intermittent claudication (IC), lesions with bilateral calcification vs. those without (peripheral arterial calcium scoring system [PACSS] 3,4 vs. PACSS 0 - 2), and CTO vs. no CTO. Propensity score matching was performed to reduce the impact of baseline variables. The 36 month endpoints were clinically driven target lesion revascularisation (CD-TLR), death, major target limb amputation, and stent patency. RESULTS: A total of 507 patients were enrolled. At 36 months, patients with CLTI had lower freedom from major amputation than patients with IC (92.6% vs. 100%, p < .001). In terms of primary patency, patients with CTO had lower patency rates than those without (63.9% vs. 77.8%, p = .003), but the difference reduced after propensity score matching (70.5% vs. 76.8%, p = .43). Primary patency was not impaired for patients with PACSS 3,4 or patients with CLTI. Freedom from CD-TLR was not significantly different among the groups and was 73.8% for CLTI vs. 78.9% for IC (p = .15), 77.6% for PACSS 3,4 vs. 78.7% for PACSS 0 - 2 (p = .55), and 75.6% for CTO vs. 81.0% for no CTO (p = .11). CONCLUSIONS: The outcome of the MIMICS-3D registry suggests that the BioMimics 3D stent is effective in the endovascular treatment of complex femoropopliteal lesions and in CLTI. Future randomised controlled trials should confirm its non-inferiority or superiority compared with existing alternatives.

BioMimics 3D vascular stent system for femoropopliteal interventions.

Background: The MIMICS-3D study aimed to assess the safety and effectiveness of the BioMimics 3D Vascular Stent System for the treatment of symptomatic femoropopliteal artery disease in a real-world patient population. Patients and methods: Consecutive participants who were scheduled for implantation of the BioMimics 3D stent were enrolled in the prospective, observational, multicenter study. The primary effectiveness outcome was freedom from clinically driven target lesion revascularization at 12 months and the primary safety outcome was a composite of major adverse events comprising death, major target limb amputation, or clinically driven target lesion revascularization at 30 days. Outcomes through 24 months are reported. Results: A total of 507 patients (70±10 years, 65.5% male sex) were enrolled and treated with the study stent. 24.0% had critical limb-threatening ischemia, lesion length was 127±92 mm, and 56.8% of lesions were totally occluded. The Kaplan-Meier (KM) estimate of freedom from clinically driven target lesion revascularization at twelve-months was 90.6% (95% CI: 87.9%-93.3%) and the 30-day primary safety outcome occurred in 1.2% (95% CI: 0.5%-2.7%) of participants. At 24 months, clinical improvement was achieved in 86.6% and the KM estimate of freedom from clinically driven target lesion revascularization was 82.8% (95% CI: 79.4%-86.4%). The KM estimate of freedom from loss of primary patency according to PSVR >2.4 was 78.6% (95% CI: 74.7%-82.4%). Survival distribution functions regarding primary patency were lower with long lesions (>150 mm; log-rank p<0.001) but did not differ significantly between participants with or without critical limb-threatening ischemia (log-rank p=0.07). Conclusions: Endovascular treatment of atherosclerotic femoropopliteal lesions with the BioMimics 3D Vascular Stent System is efficacious and safe in a real-world setting.

Treatment of Femoropopliteal Lesions With the BioMimics 3D Vascular Stent System: Two-Year Results From the MIMICS-2 Trial.

PURPOSE: To report the safety and effectiveness outcomes through 2 years of the BioMimics 3D Vascular Stent System in the treatment of symptomatic patients with atherosclerotic femoropopliteal disease. MATERIALS AND METHODS: The tubular, nitinol BioMimics 3D stent, which was designed to impart a helical shape to the arterial segment, was implanted in 271 patients (mean age 68.4±9.5 years; 180 men) with de novo femoropopliteal lesions enrolled at 43 investigational sites [31 US (n=162), 6 German (n=78), and 6 Japanese (n=31)] in the prospective, single-arm MIMICS-2 investigational device exemption trial (ClinicalTrials.gov identifier NCT02400905) between June 2015 and October 2016. Mean lesion length was 81.2±38.4 mm, 30.0% of patients had total occlusions, and 45.9% had moderate to severe calcification. Primary safety and effectiveness endpoints were compared at 1 year with prespecified objective performance goals (OPGs) set by the VIVA Physicians organization. Outcomes through 2 years are reported. RESULTS: The primary effectiveness endpoint of 12-month primary stent patency was met by 182 of 249 patients (73.1%, 95% CI 67.3% to 78.2%), exceeding the OPG of 66%. The primary safety endpoint of 30-day freedom from major adverse events (MAEs) was met in 268 of 269 patients (99.6%, 95% CI 97.7% to 100%), exceeding the OPG of 88%. Kaplan-Meier estimates of freedom from loss of primary patency were 83.1% at 12 months and 70.2% at 24 months, freedom from MAEs estimates were 86.9% at 12 months and 79.2% at 24 months, and freedom from clinically-driven target lesion revascularization estimates were 88.0% at 12 months and 83.0% at 24 months. At 24 months, 88.2% of patients showed improvement of ≥1 Rutherford category; the ankle-brachial index was >0.9 for 64.4% vs 11.3% at baseline. There were no cases of stent fracture. CONCLUSION: Through 24 months, the BioMimics 3D Vascular Stent System provided safe and effective treatment for femoropopliteal lesions in patients with symptomatic peripheral artery disease.

Cooperative Activity of GABP with PU.1 or C/EBPε Regulates Lamin B Receptor Gene Expression, Implicating Their Roles in Granulocyte Nuclear Maturation.

Nuclear segmentation is a hallmark feature of mammalian neutrophil differentiation, but the mechanisms that control this process are poorly understood. Gene expression in maturing neutrophils requires combinatorial actions of lineage-restricted and more widely expressed transcriptional regulators. Examples include interactions of the widely expressed ETS transcription factor, GA-binding protein (GABP), with the relatively lineage-restricted E-twenty-six (ETS) factor, PU.1, and with CCAAT enhancer binding proteins, C/EBPα and C/EBPε. Whether such cooperative interactions between these transcription factors also regulate the expression of genes encoding proteins that control nuclear segmentation is unclear. We investigated the roles of ETS and C/EBP family transcription factors in regulating the gene encoding the lamin B receptor (LBR), an inner nuclear membrane protein whose expression is required for neutrophil nuclear segmentation. Although C/EBPε was previously shown to bind the Lbr promoter, surprisingly, we found that neutrophils derived from Cebpe null mice exhibited normal Lbr gene and protein expression. Instead, GABP provided transcriptional activation through the Lbr promoter in the absence of C/EBPε, and activities supported by GABP were greatly enhanced by either C/EBPε or PU.1. Both GABP and PU.1 bound Ets sites in the Lbr promoter in vitro, and in vivo within both early myeloid progenitors and differentiating neutrophils. These findings demonstrate that GABP, PU.1, and C/EBPε cooperate to control transcription of the gene encoding LBR, a nuclear envelope protein that is required for the characteristic lobulated morphology of mature neutrophils.

Characterization of neutrophils and macrophages from ex vivo-cultured murine bone marrow for morphologic maturation and functional responses by imaging flow cytometry.

Neutrophils and macrophages differentiate from common myeloid progenitors in the bone marrow, where they undergo nuclear morphologic changes during maturation. During this process, both cell types acquire critical innate immune functions that include phagocytosis of pathogens, and for neutrophils the release of nuclear material called nuclear extracellular traps (NETs). Primary cells used to study these functions are typically purified from mature mouse tissues, but bone marrow-derived ex vivo cultures provide more abundant numbers of progenitors and functionally mature cells. Routine analyses of these cells use conventional microscopy and flow cytometry, which present limitations; microscopy is laborious and subjective, whereas flow cytometry lacks spatial resolution. Here we describe methods to generate enriched populations of neutrophils or macrophages from cryopreserved mouse bone marrow cultured ex vivo, and to use imaging flow cytometry that combines the resolution of microscopy with flow cytometry to analyze cells for morphologic features, phagocytosis, and NETosis.

Ingested engineered nanomaterials: state of science in nanotoxicity testing and future research needs.

BACKGROUND: Engineered nanomaterials (ENM) are used extensively in food products to fulfill a number of roles, including enhancement of color and texture, for nutritional fortification, enhanced bioavailability, improved barrier properties of packaging, and enhanced food preservation. Safety assessment of ingested engineered nanomaterials (iENM) has gained interest in the nanotoxicology community in recent years. A variety of test systems and approaches have been used for such evaluations, with in vitro monoculture cell models being the most common test systems, owing to their low cost and ease-of-use. The goal of this review is to systematically assess the current state of science in toxicological testing of iENM, with particular emphasis on model test systems, their physiological relevance, methodological strengths and challenges, realistic doses (ranges and rates), and then to identify future research needs and priorities based on these assessments. METHODS: Extensive searches were conducted in Google Scholar, PubMed and Web of Science to identify peer-reviewed literature on safety assessment of iENM over the last decade, using keywords such as "nanoparticle", "food", "toxicity", and combinations thereof. Relevant literature was assessed based on a set of criteria that included the relevance of nanomaterials tested; ENM physicochemical and morphological characterization; dispersion and dosimetry in an in vitro system; dose ranges employed, the rationale and dose realism; dissolution behavior of iENM; endpoints tested, and the main findings of each study. Observations were entered into an excel spreadsheet, transferred to Origin, from where summary statistics were calculated to assess patterns, trends, and research gaps. RESULTS: A total of 650 peer-reviewed publications were identified from 2007 to 2017, of which 39 were deemed relevant. Only 21% of the studies used food grade nanomaterials for testing; adequate physicochemical and morphological characterization was performed in 53% of the studies. All in vitro studies lacked dosimetry and 60% of them did not provide a rationale for the doses tested and their relevance. Only 12% of the studies attempted to consider the dissolution kinetics of nanomaterials. Moreover, only 1 study attempted to prepare and characterize standardized nanoparticle dispersions. CONCLUSION: We identified 5 clusters of factors deemed relevant to nanotoxicology of food-grade iENM: (i) using food-grade nanomaterials for toxicity testing; (ii) performing comprehensive physicochemical and morphological characterization of iENM in the dry state, (iii) establishing standard NP dispersions and their characterization in cell culture medium, (iv) employing realistic dose ranges and standardized in vitro dosimetry models, and (v) investigating dissolution kinetics and biotransformation behavior of iENM in synthetic media representative of the gastrointestinal (GI) tract fluids, including analyses in a fasted state and in the presence of a food matrix. We discussed how these factors, when not considered thoughtfully, could influence the results and generalizability of in vitro and in vivo testing. We conclude with a set of recommendations to guide future iENM toxicity studies and to develop/adopt more relevant in vitro model systems representative of in vivo animal and human iENM exposure scenarios.

SRF is required for neutrophil migration in response to inflammation.

Serum response factor (SRF) is a ubiquitously expressed transcription factor and master regulator of the actin cytoskeleton. We have previously shown that SRF is essential for megakaryocyte maturation and platelet formation and function. Here we elucidate the role of SRF in neutrophils, the primary defense against infections. To study the effect of SRF loss in neutrophils, we crossed Srf(fl/fl) mice with select Cre-expressing mice and studied neutrophil function in vitro and in vivo. Despite normal neutrophil numbers, neutrophil function is severely impaired in Srf knockout (KO) neutrophils. Srf KO neutrophils fail to polymerize globular actin to filamentous actin in response to N-formyl-methionine-leucine-phenylalanine, resulting in significantly disrupted cytoskeletal remodeling. Srf KO neutrophils fail to migrate to sites of inflammation in vivo and along chemokine gradients in vitro. Polarization in response to cytokine stimuli is absent and Srf KO neutrophils show markedly reduced adhesion. Integrins play an essential role in cellular adhesion, and although integrin expression levels are maintained with loss of SRF, integrin activation and trafficking are disrupted. Migration and cellular adhesion are essential for normal cell function, but also for malignant processes such as metastasis, underscoring an essential function for SRF and its pathway in health and disease.

Evaluation of a noise reduction imaging technology in iliac digital subtraction angiography: noninferior clinical image quality with lower patient and scatter dose.

PURPOSE: To determine whether equivalent-quality images can be obtained from digital subtraction angiography (DSA) of the iliac artery after implementation of a novel imaging technology that reduces patient and scatter x-ray dose. MATERIALS AND METHODS: Imaging using two randomly ordered DSA runs was performed in 51 adults scheduled for iliac artery angiography or intervention or both. One DSA run used standard acquisition chain and image processing algorithms (referred to as " reference DSA"), and the other DSA run used dose-reduction and real-time advanced image noise reduction technology (referred to as "study DSA"). The quality of each pair of runs, consecutively performed without changes in working projection or injection parameters, was independently rated by five radiologists blinded to the imaging technology used. Patient radiation dose was evaluated using air kerma and dose area product, and scatter dose was evaluated using three dosimeters (DoseAware, Philips Healthcare, Best, The Netherlands), located at fixed positions. RESULTS: Comparable image pairs were available in 48 patients. There were 44 patients undergoing treatment involving the common (n = 33) or external (n = 29) iliac arteries. Study DSA images were rated as equal to or better than reference DSA images for 96% of comparisons, with an average overall agreement among raters of 0.93 (95% confidence interval, 0.65-0.96). Mean patient radiation dose (n = 48) and scatter dose rate for the three dosimeters (n = 50) was 83% ± 5 and 69% ± 10 lower, respectively, using the study technology (P < .001). CONCLUSIONS: Iliac artery DSA performed using a dose-reduction and real-time advanced image noise reduction technology results in image quality that is noninferior to conventional DSA but with significantly lower patient and scatter radiation exposure (P < .001).

Absent right common carotid artery with stenting of symptomatic internal carotid artery stenosis.

Absent common carotid artery with independent origin of internal and external carotid arteries from the subclavian artery is a rare but recognized phenomenon. We describe one such case with an associated symptomatic proximal high-grade stenosis of the right internal carotid artery. The abnormal carotid anatomy was not initially well appreciated, resulting in a failed surgical exploration and subsequent successful endovascular carotid stenting. To our knowledge, this is the first reported case of carotid stent in a right internal carotid artery originating from the subclavian artery.

Lamin B receptor regulates the growth and maturation of myeloid progenitors via its sterol reductase domain: implications for cholesterol biosynthesis in regulating myelopoiesis.

Lamin B receptor (LBR) is a bifunctional nuclear membrane protein with N-terminal lamin B and chromatin-binding domains plus a C-terminal sterol Δ(14) reductase domain. LBR expression increases during neutrophil differentiation, and deficient expression disrupts neutrophil nuclear lobulation characteristic of Pelger-Huët anomaly. Thus, LBR plays a critical role in regulating myeloid differentiation, but how the two functional domains of LBR support this role is currently unclear. We previously identified abnormal proliferation and deficient functional maturation of promyelocytes (erythroid, myeloid, and lymphoid [EML]-derived promyelocytes) derived from EML-ic/ic cells, a myeloid model of ichthyosis (ic) bone marrow that lacks Lbr expression. In this study, we provide new evidence that cholesterol biosynthesis is important to myeloid cell growth and is supported by the sterol reductase domain of Lbr. Cholesterol biosynthesis inhibitors caused growth inhibition of EML cells that increased in EML-derived promyelocytes, whereas cells lacking Lbr exhibited complete growth arrest at both stages. Lipid production increased during wild-type neutrophil maturation, but ic/ic cells exhibited deficient levels of lipid and cholesterol production. Ectopic expression of a full-length Lbr in EML-ic/ic cells rescued both nuclear lobulation and growth arrest in cholesterol starvation conditions. Lipid production also was rescued, and a deficient respiratory burst was corrected. Expression of just the C-terminal sterol reductase domain of Lbr in ic/ic cells also improved each of these phenotypes. Our data support the conclusion that the sterol Δ(14) reductase domain of LBR plays a critical role in cholesterol biosynthesis and that this process is essential to both myeloid cell growth and functional maturation.

Characteristics of ischemic brain lesions after stenting or endarterectomy for symptomatic carotid artery stenosis: results from the international carotid stenting study-magnetic resonance imaging substudy.

BACKGROUND AND PURPOSE: In a substudy of the International Carotid Stenting Study (ICSS), more patients had new ischemic brain lesions on diffusion-weighted magnetic resonance imaging (MRI) after stenting (CAS) than after endarterectomy (CEA). In the present analysis, we compared characteristics of diffusion-weighted MRI lesions. METHODS: Number, individual and total volumes, and location of new diffusion-weighted MRI lesions were compared in patients with symptomatic carotid stenosis randomized to CAS (n=124) or CEA (n=107) in the ICSS-MRI substudy. RESULTS: CAS patients had higher lesion numbers than CEA patients (1 lesion, 15% vs 8%; 2-5 lesions, 19% vs 5%; >5 lesions, 16% vs 4%). The overall risk ratio for the expected lesion count with CAS versus CEA was 8.8 (95% confidence interval, 4.4-17.5; P<0.0001) and significantly increased among patients with lower blood pressure at randomization, diabetes mellitus, stroke as the qualifying event, left-side stenosis, and if patients were treated at centers routinely using filter-type protection devices during CAS. Individual lesions were smaller in the CAS group than in the CEA group (P<0.0001). Total lesion volume per patient did not differ significantly. Lesions in the CAS group were more likely to occur in cortical areas and subjacent white matter supplied by leptomeningeal arteries than lesions in the CEA group (odds ratio, 4.2; 95% confidence interval, 1.7-10.2; P=0.002). CONCLUSIONS: Compared with patients undergoing CEA, patients treated with CAS had higher numbers of periprocedural ischemic brain lesions, and lesions were smaller and more likely to occur in cortical areas and subjacent white matter. These findings may reflect differences in underlying mechanisms of cerebral ischemia.

Assessment of reverse flow as a means of cerebral protection during carotid artery stent placement with diffusion-weighted and transcranial Doppler imaging.

PURPOSE: To assess the effectiveness of flow reversal as an alternative means of cerebral protection by using transcranial Doppler recordings and diffusion-weighted imaging (DWI) as surrogate markers of brain injury. MATERIALS AND METHODS: Eighteen patients with symptomatic carotid artery disease were recruited. Magnetic resonance imaging was performed before the intervention and at 3 and 24 hours and 30 days after the intervention to detect new ischemic lesions with DWI. Transcranial Doppler recordings were made during the procedure to assess for microembolic signals (MESs). Data were compared against data from a historical control cohort of patients who underwent CAS placement with or without filter protection (n = 15 each) under the same protocol in a different study. RESULTS: There were fewer periprocedural new lesions on DWI in the reverse-flow cohort compared with the historical control cohort with filter protection (P = .084). Reverse flow revealed significantly fewer MESs during the whole procedure compared with the filter-protected group (P = .01) but not the unprotected group (P = .55). There was a marked decrease in MES counts for reverse flow protection during the embologenic stages of the procedure (P = .004). CONCLUSIONS: Use of the reverse flow device was associated with fewer overall lesions on DWI and proportionately fewer positive scans compared with the use of filter-type devices (P = .08, not significant). Transcranial Doppler recordings demonstrated a significant reduction in embolization to the brain during carotid artery stent placement with the use of reverse-flow cerebral protection.

Evaluation of cytotoxic, genotoxic and inflammatory responses of nanoparticles from photocopiers in three human cell lines.

BACKGROUND: Photocopiers emit nanoparticles with complex chemical composition. Short-term exposures to modest nanoparticle concentrations triggered upper airway inflammation and oxidative stress in healthy human volunteers in a recent study. To further understand the toxicological properties of copier-emitted nanoparticles, we studied in-vitro their ability to induce cytotoxicity, pro-inflammatory cytokine release, DNA damage, and apoptosis in relevant human cell lines. METHODS: Three cell types were used: THP-1, primary human nasal- and small airway epithelial cells. Following collection in a large volume photocopy center, nanoparticles were extracted, dispersed and characterized in the cell culture medium. Cells were doped at 30, 100 and 300 µg/mL administered doses for up to 24 hrs. Estimated dose delivered to cells, was ~10% and 22% of the administered dose at 6 and 24 hrs, respectively. Gene expression analysis of key biomarkers was performed using real time quantitative PCR (RT-qPCR) in THP-1 cells at 5 µg nanoparticles/mL for 6-hr exposure for confirmation purposes. RESULTS: Multiple cytokines, GM-CSF, IL-1ß, IL-6, IL-8, IFNγ, MCP-1, TNF-α and VEGF, were significantly elevated in THP-1 cells in a dose-dependent manner. Gene expression analysis confirmed up-regulation of the TNF-α gene in THP-1 cells, consistent with cytokine findings. In both primary epithelial cells, cytokines IL-8, VEGF, EGF, IL-1α, TNF-α, IL-6 and GM-CSF were significantly elevated. Apoptosis was induced in all cell lines in a dose-dependent manner, consistent with the significant up-regulation of key apoptosis-regulating genes P53 and Casp8 in THP-1 cells. No significant DNA damage was found at any concentration with the comet assay. Up-regulation of key DNA damage and repair genes, Ku70 and Rad51, were also observed in THP-1 cells, albeit not statistically significant. Significant up-regulation of the key gene HO1 for oxidative stress, implicates oxidative stress induced by nanoparticles. CONCLUSIONS: Copier-emitted nanoparticles induced the release of pro-inflammatory cytokines, apoptosis and modest cytotoxicity but no DNA damage in all three-human cell lines. Taken together with gene expression data in THP-1 cells, we conclude that these nanoparticles are directly responsible for inflammation observed in human volunteers. Further toxicological evaluations of these nanoparticles, including across different toner formulations, are warranted.

Toxicological effects of PM0.25-2.0 particles collected from a photocopy center in three human cell lines.

Printing devices such as photocopiers and printers emit predominantly nanoparticles, which may aggregate with time to form PM0.25-2.0 particles. To date, there are no reports on cytotoxic or genotoxic effects of PM0.25-2.0 particles emitted from photocopiers. To investigate the ability of PM0.25-2 fraction emitted from photocopiers, induce pro-inflammatory cytokines, DNA damage and apoptosis in different human-derived cell lines. Three cell types, i.e. a THP-1 line, primary human nasal and small airway epithelial cells, were used. The airborne PM0.25-2.0 size fraction collected from a photocopy center was characterized for its physicochemical and morphological properties, dispersed in culture media and cells were treated with 30, 100 or 300 µg/ml doses. Levels of 13 cytokines and chemokines in the culture medium harvested at 6 and 24 h of treatment were measured using Luminex cytokine kits. In cells harvested at the same timepoints, DNA damage in cells was studied by a Comet assay, and apoptosis was measured by cytofluorimetry using an Annexin V staining kit. The results indicate that in THP-1 cells, several cytokines (IL-6, IL-8, TNFα and IL-1ß) were significantly elevated. Only IL-8 was significantly elevated in the primary nasal and small airway cells. Cells exposed to PM0.25-2.0 underwent apoptosis in a dose-dependent manner, but no significant differences were found in the extent of DNA damage at either timepoint. Airborne PM0.25-2.0 collected at one photocopier center was capable of inducing several pro-inflammatory cytokines and apoptosis, but no genotoxicity, in all cell lines suggesting a role for PM0.25-2.0 in our previously documented airway inflammation in human volunteers. Further toxicological evaluations of these particles across different toner manufacturers are warranted.

CXCR2 Antagonist RIST4721 Acts as a Potent Chemotaxis Inhibitor of Mature Neutrophils Derived from Ex Vivo-Cultured Mouse Bone Marrow.

Neutrophils act as critical mediators of innate immunity, which depends on their rapid responses to chemokines followed by their migration towards sites of infection during chemotaxis. Chemokine receptors expressed on the surface of neutrophils mediate chemotaxis by activating contractile machinery as the cells escape from capillary beds and then attack pathogens. Neutrophils also contribute to inflammatory responses, which support pathogen destruction but can lead to acute and chronic inflammatory disorders. CXCR2, a G-protein-coupled chemokine receptor expressed on both myeloid and epithelial cells, is well-characterized for its capacities to bind multiple chemokines, including interleukin-8 and growth-related oncogene alpha in humans or keratinocyte chemokine (KC) in mice. Here we show that a small molecule CXCR2 antagonist termed RIST4721 can effectively inhibit KC-stimulated chemotaxis by neutrophils derived from ex vivo-cultured mouse bone marrow in a potent and dose-dependent manner. Antagonistic properties of RIST4721 are thoroughly characterized, including the maximal, half-maximal and minimum concentrations required to inhibit chemotaxis. Importantly, RIST4721-treated neutrophils exhibit robust phagocytosis and reactive oxygen species production, confirming drug specificity to chemotaxis inhibition. Together our data indicate that RIST4721 acts to inhibit inflammation mediated and potentiated by neutrophils and therefore promises to facilitate treatment of a host of inflammatory conditions.

Quantitatively Assessing the Respiratory Burst in Innate Immune Cells.

The respiratory burst is a rapid cellular consumption of oxygen resulting in abundant production of reactive oxygen species (ROS), most often associated with primary mediators of innate immunity, neutrophils and macrophages. These myeloid cells convert ROS into potent antimicrobial oxidants that efficiently kill pathogens. The respiratory burst also can have destructive consequences, as ROS are well known to support chronic inflammation and aberrant autoimmune responses. Interestingly, ROS perform conflicting roles in the tumor microenvironment; ROS and derived cytotoxic products can destroy cancer cells but also suppress important tumor-fighting functions of T cells or natural killer cells, or yield mutagenized proteins that can promote tumorigenesis or support tumor cell growth. Moreover, high numbers of neutrophils or macrophages in tumors are associated with poor prognosis. Therefore, accurate and quantitative assays to assess the respiratory burst are an important tool for measuring ROS production by neutrophils or cells of the monocyte/macrophage system, each recently identified in the tumor microenvironment. Described are methods to derive mouse or human models of neutrophils or macrophages, which are then used in a detailed assay to quantitatively measure ROS produced by either cell type using luminescence-enhanced reagents and a multi-well platform along with different stimulants that cause rapid ROS production.

BioMimics 3D Stent in Femoropopliteal Lesions: 3-Year Outcomes with Propensity Matching for Drug-Coated Balloons.

BACKGROUND: Through its helical centreline geometry, the BioMimics 3D vascular stent system is designed for the mobile femoropopliteal region, aiming to improve long-term patency and the risk of stent fractures. METHODS: MIMICS 3D is a prospective, European, multi-centre, observational registry to evaluate the BioMimics 3D stent in a real-world population through 3 years. A propensity-matched comparison was performed to investigate the effect of the additional use of drug-coated balloons (DCB). RESULTS: The MIMICS 3D registry enrolled 507 patients (518 lesion, length 125.9 ± 91.0 mm). At 3 years, the overall survival was 85.2%, freedom from major amputation 98.5%, freedom from clinically driven target lesion revascularisation 78.0%, and primary patency 70.2%. The propensity-matched cohort included 195 patients in each cohort. At 3-year follow-up, there was no statistically significant difference in clinical outcomes, such as overall survival (87.9% in the DCB vs. 85.1% in the no DCB group), freedom from major amputation (99.4% vs. 97.2%), clinically driven TLR (76.4% vs. 80.3%), and primary patency (68.5% vs. 74.4%). CONCLUSION: The MIMICS 3D registry showed good 3-year outcomes of the BioMimics 3D stent in femoropopliteal lesions, demonstrating the safety and performance of this device under real-world conditions, whether used alone or in combination with a DCB.

Safety and performance of a novel implantable sensor in the inferior vena cava under acute and chronic intravascular volume modulation.

AIMS: The management of congestion is one of the key treatment targets in heart failure. Assessing congestion is, however, difficult. The purpose of this study was to investigate the safety and dynamic response of a novel, passive, inferior vena cava (IVC) sensor in a chronic ovine model. METHODS AND RESULTS: A total of 20 sheep divided into three groups were studied in acute and chronic in vivo settings. Group I and Group II included 14 sheep in total with 12 sheep receiving the sensor and two sheep receiving a control device (IVC filter). Group III included an additional six animals for studying responses to volume challenges via infusion of blood and saline solutions. Deployment was 100% successful with all devices implanted; performing as expected with no device-related complications and signals were received at all observations. At similar volume states no significant differences in IVC area normalized to absolute area range were measured (55 ± 17% on day 0 and 62 ± 12% on day 120, p = 0.51). Chronically, the sensors were completely integrated with a thin, reendothelialized neointima with no loss of sensitivity to infused volume. Normalized IVC area changed significantly from 25 ± 17% to 43 ± 11% (p = 0.007) with 300 ml infused. In contrast, right atrial pressure required 1200 ml of infused volume prior to a statistically significant change from 3.1 ± 2.6 mmHg to 7.5 ± 2.0 mmHg (p = 0.02). CONCLUSION: In conclusion, IVC area can be measured remotely in real-time using a safe, accurate, wireless, and chronic implantable sensor promising to detect congestion with higher sensitivity than filling pressures.

Expression Levels of Lamin A or C Are Critical to Nuclear Maturation, Functional Responses, and Gene Expression Profiles in Differentiating Mouse Neutrophils.

Neutrophils mediate critical innate immune responses by migrating to sites of infection or inflammation, phagocytosing microorganisms, and releasing an arsenal of antimicrobial agents, including reactive oxygen species. These functions are shared by other innate immune cell types, but an interesting feature of neutrophils is their hallmark lobulated nuclei. Although why this bizarre nuclear shape forms is still being elucidated, studies of two intermediate filament proteins that associate with the nuclear envelope, lamin A and C, indicate that expression levels of these proteins govern nuclear maturation. These A-type lamins also modulate nuclear stiffness, the loss of which may be critical to the migration of not only neutrophils but also cancer cells that become prone to metastasis. We investigated whether increased expression of either lamin A or C affects neutrophil nuclear morphologic maturation, but more importantly we tested whether overexpression of either lamin also affects neutrophil functional responses, using two mouse myeloid progenitor models that can be induced toward functionally responsive neutrophil-like cells. Collectively, our results demonstrate that overexpression of either lamin A or C not only disrupts nuclear lobulation but also causes aberrant functional responses critical to innate immunity, including chemotaxis, phagocytosis, and reactive oxygen species production. Moreover, the lamin A-overexpressing cells exhibit decreased expression of a critical NADPH oxidase complex factor, gp91phox, and transcriptomic profiling demonstrated differential expression of a number of myeloid differentiation and functional pathway components. Taken together, these data demonstrate that A-type lamin expression levels modulate not only nuclear morphologic features but also gene expression changes as neutrophils mature.