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BACKGROUND: Innate lymphoid cells type 2 (ILC2s) play critical homeostatic functions in peripheral tissues. ILC2s reside in perivascular niches and limit atherosclerosis development. OBJECTIVES: ILC2s also reside in the pericardium but their role in postischemic injury is unknown. METHODS: We examined the role of ILC2 in a mouse model of myocardial infarction (MI), and compared mice with or without genetic deletion of ILC2. We determined infarct size using histology and heart function using echocardiography. We assessed cardiac ILC2 using flow cytometry and RNA sequencing. Based on these data, we devised a therapeutic strategy to activate ILC2 in mice with acute MI, using exogenous interleukin (IL)-2. We also assessed the ability of low-dose IL-2 to activate ILC2 in a double-blind randomized clinical trial of patients with acute coronary syndromes (ACS). RESULTS: We found that ILC2 levels were increased in pericardial adipose tissue after experimental MI, and genetic ablation of ILC2 impeded the recovery of heart function. RNA sequencing revealed distinct transcript signatures in ILC2, and pointed to IL-2 axis as a major upstream regulator. Treatment of T-cell-deficient mice with IL-2 (to activate ILC2) significantly improved the recovery of heart function post-MI. Administration of low-dose IL-2 to patients with ACS led to activation of circulating ILC2, with significant increase in circulating IL-5, a prototypic ILC2-derived cytokine. CONCLUSIONS: ILC2s promote cardiac healing and improve the recovery of heart function after MI in mice. Activation of ILC2 using low-dose IL-2 could be a novel therapeutic strategy to promote a reparative response after MI.

Radiomics, quantitative feature extraction from radiological images, can improve disease diagnosis and prognostication. However, radiomic features are susceptible to image acquisition and segmentation variability. Ideally, only features robust to these variations would be incorporated into predictive models, for good generalisability. We extracted 93 radiomic features from carotid artery computed tomography angiograms of 41 patients with cerebrovascular events. We tested feature robustness to region-of-interest perturbations, image pre-processing settings and quantisation methods using both single- and multi-slice approaches. We assessed the ability of the most robust features to identify culprit and non-culprit arteries using several machine learning algorithms and report the average area under the curve (AUC) from five-fold cross validation. Multi-slice features were superior to single for producing robust radiomic features (67 vs. 61). The optimal image quantisation method used bin widths of 25 or 30. Incorporating our top 10 non-redundant robust radiomics features into ElasticNet achieved an AUC of 0.73 and accuracy of 69% (compared to carotid calcification alone [AUC: 0.44, accuracy: 46%]). Our results provide key information for introducing carotid CT radiomics into clinical practice. If validated prospectively, our robust carotid radiomic set could improve stroke prediction and target therapies to those at highest risk.

Background Regulatory T lymphocytes (Tregs) are critical for immune homeostasis. Pre-clinical models have demonstrated that Tregs can modulate post-ischaemic immune responses and promote myocardial healing. Patients with ischaemic heart disease (IHD) display reduced anti-inflammatory Tregs and increased pro-inflammatory effector T cells (Teffs). Low-dose interleukin-2 (ld-IL2) has been shown to increase Tregs in patients with autoimmune diseases but is currently contraindicated in patients with IHD. Purpose To assess the safety and pharmacodynamic effect of ld-IL-2 in patients with IHD. Methods LILACS was a prospective, randomised, double-blind, placebo-controlled, dose-escalation, Phase I/II clinical trial, which tested ld-IL-2 (aldesleukin) given once daily subcutaneously, for five consecutive days. In Part A, 25 patients with stable IHD were randomised (drug:placebo ratio of 3:2) in 5 dose groups (0.3, 0.6, 1.2, 2.4 and 3x106 IU/day); whilst in Part B, 16 patients with non-ST elevation myocardial infarction (NSTEMI) were randomised (drug:placebo ratio of 6:2) in two dose groups (1.5 and 2.5x106 IU/day). Follow up was performed the day after dosing and again 7 days later. Doses were determined after blinded review. An independent committee reviewed unblinded data prior to commencing Part B. The primary endpoint was safety in parts A and B. Additionally in Part B, a co-primary endpoint was to calculate the dose required to increase Tregs by 75%. [NCT03113773] Results Ld-IL2 was well tolerated for all dose groups with the commonest adverse events being mild injection site reactions. Two serious adverse events, not considered to be drug related, occurred in Part B – one prior to dosing and resulting in withdrawal. The other was a recurrent NSTEMI after dosing ended in a patient with severe triple vessel coronary artery disease awaiting urgent bypass surgery. In Part A, Tregs increased with dose escalation whilst no Teff increases were noted (Figure 1A). In Part B, patients treated with 1.5 and 2.5x106 IU/day doses had a median increase in Tregs of 80.5% (CI 36.2–124.7%, p=0.003) and 108.3% (CI 55.3–161.3%, p=0.002) respectively (Figure 1B). A linear regression model estimated an increase of 43.3% (CI 23.6–63.0%, p=0.0003) per unit dose. The estimated dose to achieve a 75% increase in Tregs was 1.46x106 IU/day (CI 1.06–1.87). No increase in Teffs cells were seen however, a dose-dependent decrease was measured in B cells, whilst NK cells and eosinophils increased at the top 2.5 and 3x106 IU/day dose. A panel of 29 cytokines and chemokines showed a dose-dependent type 1 and 2 cytokine response. Single-cell RNA sequencing was performed on immune cells before and after dosing. Conclusions Ld-IL2 was safe and well-tolerated. An induction dose of 1.5x106 IU per day for 5 days provided an effective expansion of Tregs without increasing Teffs. This work provides important data for the future therapeutic use of ld-IL-2 which is ongoing. Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): Medical Research Council, British Heart Foundation Cambridge Centre of Excellence

Atherosclerosis is a systemic inflammatory disease typified by the development of lipid-rich atheroma (plaques), the rupture of which are a major cause of myocardial infarction and stroke. Anatomical evaluation of the plaque considering only the degree of luminal stenosis overlooks features associated with vulnerable plaques, such as high-risk morphological features or pathophysiology, and hence risks missing vulnerable or ruptured non-stenotic plaques. Consequently, there has been interest in identifying these markers of vulnerability using either MRI for morphology, or positron emission tomography (PET) for physiological processes involved in atherogenesis. The advent of hybrid PET/MRI scanners offers the potential to combine the strengths of PET and MRI to allow comprehensive assessment of the atherosclerotic plaque. This review will discuss the principles and technical aspects of hybrid PET/MRI assessment of atherosclerosis, and consider how combining the complementary modalities of PET and MRI has already furthered our understanding of atherogenesis, advanced drug development, and how it may hold potential for clinical application.

PET imaging is able to harness biological processes to characterise high-risk features of atherosclerotic plaque prone to rupture. Current radiotracers are able to track inflammation, microcalcification, hypoxia, and neoangiogenesis within vulnerable plaque. 18 F-fluorodeoxyglucose (18 F-FDG) is the most commonly used radiotracer in vascular studies and is employed as a surrogate marker of plaque inflammation. Increasingly, 18 F-FDG and other PET tracers are also being used to provide imaging endpoints in cardiovascular interventional trials. The evolution of novel PET radiotracers, imaging protocols, and hybrid scanners are likely to enable more efficient and accurate characterisation of high-risk plaque. This review explores the role of PET imaging in atherosclerosis with a focus on PET tracers utilised in clinical research and the applications of PET imaging to cardiovascular drug development.

Two recent studies investigating the use of chaperones and chaperone policies in UK emergency departments suggest that the vast majority of departments do not have a formal chaperone policy.1 2 Furthermore, one of the studies suggests that doctors regularly conduct intimate examinations on patients without a chaperone being present.2 We report the results of an audit of junior doctors' use of chaperones for …

In a recent genome-wide study to identify androgen receptor target genes we found that the AR promotes tumor growth by enhancing the expression and activity of enzymes required for metabolic biosynthesis. This raises the possibility for effective therapeutic approaches directed towards AR target genes. Kinases are well-established drug targets. In this study we identify androgen regulated kinome and show that an important androgen regulated metabolic kinase is a drug target in prostate cancer. Our proteome study shows that this kinase interacts with the androgen receptor and regulates AR stability. Inhibition of this kinase significantly reduces AR protein levels and suppresses prostate cancer growth in cell-lines and ex vivo cultures. In clinical prostate cancer this kinase is highly over-expressed in metastatic prostate cancers and inhibition represses metastatic potential of prostate cancer cells. Our study therefore establishes this kinase for the first time as an AR target gene that regualtes AR itself as part of feedback loop and makes a case for further investigation of its inhibitors as novel AR antagonists in both localised and advanced disease. Citation Information: Mol Cancer Ther 2013;12(11 Suppl):B133. Citation Format: Mohammad asim, Charlie Massie, Heather Zecchini, Ajoeb Baridi, Nelma Gomes, Hisham Mohammed, Vincent Zecchini, Basetti Madhu, Arham Qureshi, Roslin Russell, Wiebke Hessenkemper, Rouchelle Sriranjan, Carrie Yang, Andy Lynch, Elena Gregorengko, Rory Stark, Paul Rennie, John Griffiths, Aria Baniahmad, Jasol Carroll, Ian Mills, David Neal. Regulation of the androgen receptor function by a metabolic kinase in prostate cancer. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr B133.