Efficacy and safety of MAS825 (anti-IL-1ß/IL-18) in COVID-19 patients with pneumonia and impaired respiratory function.

MAS825, a bispecific IL-1ß/IL-18 monoclonal antibody, could improve clinical outcomes in COVID-19 pneumonia by reducing inflammasome-mediated inflammation. Hospitalized non-ventilated patients with COVID-19 pneumonia (n = 138) were randomized (1:1) to receive MAS825 (10 mg/kg single i.v.) or placebo in addition to standard of care (SoC). The primary endpoint was the composite Acute Physiology and Chronic Health Evaluation II (APACHE II) score on Day 15 or on the day of discharge (whichever was earlier) with worst-case imputation for death. Other study endpoints included safety, C-reactive protein (CRP), SARS-CoV-2 presence, and inflammatory markers. On Day 15, the APACHE II score was 14.5 ± 1.87 and 13.5 ± 1.8 in the MAS825 and placebo groups, respectively (P = 0.33). MAS825 + SoC led to 33% relative reduction in intensive care unit (ICU) admissions, ~1 day reduction in ICU stay, reduction in mean duration of oxygen support (13.5 versus 14.3 days), and earlier clearance of virus on Day 15 versus placebo + SoC group. On Day 15, compared with placebo group, patients treated with MAS825 + SoC showed a 51% decrease in CRP levels, 42% lower IL-6 levels, 19% decrease in neutrophil levels, and 16% lower interferon-γ levels, indicative of IL-1ß and IL-18 pathway engagement. MAS825 + SoC did not improve APACHE II score in hospitalized patients with severe COVID-19 pneumonia; however, it inhibited relevant clinical and inflammatory pathway biomarkers and resulted in faster virus clearance versus placebo + SoC. MAS825 used in conjunction with SoC was well tolerated. None of the adverse events (AEs) or serious AEs were treatment-related.

Low-dose IL-2 enhances the generation of IL-10-producing immunoregulatory B cells.

Dysfunction of interleukin-10 producing regulatory B cells has been associated with the pathogenesis of autoimmune diseases, but whether regulatory B cells can be therapeutically induced in humans is currently unknown. Here we demonstrate that a subset of activated B cells expresses CD25, and the addition of low-dose recombinant IL-2 to in vitro stimulated peripheral blood and splenic human B cells augments IL-10 secretion. Administration of low dose IL-2, aldesleukin, to patients increases IL-10-producing B cells. Single-cell RNA sequencing of circulating immune cells isolated from low dose IL2-treated patients reveals an increase in plasmablast and plasma cell populations that are enriched for a regulatory B cell gene signature. The transcriptional repressor BACH2 is significantly down-regulated in plasma cells from IL-2-treated patients, BACH2 binds to the IL-10 gene promoter, and Bach2 depletion or genetic deficiency increases B cell IL-10, implicating BACH2 suppression as an important mechanism by which IL-2 may promote an immunoregulatory phenotype in B cells.

Minimally Invasive Ventriculo-Cholecystic Shunt Placement Utilizing Combined Ultrasound and Fluoroscopic Guidance.

For the management of hydrocephalus with ventricular cerebrospinal fluid (CSF) shunting, multiple therapeutic options are available. Among these routes, the most commonly used are ventriculo-peritoneal, ventriculo-atrial, and ventriculo-pleural, while ventriculo-cholecystic is a less common option. Although ventriculo-peritoneal is accepted as the first option, ventriculo-cholecystic shunting may be performed in patients who are poor candidates for other routes of shunt placement. Open cholecystic shunt placement may be contraindicated in patients who have undergone previous surgeries or other comorbidities. Here, we present the case of a 25-year-old female with a complex medical history who presented with a posterior fossa intraparenchymal hemorrhage and subsequent hydrocephalus. She was unable to undergo a ventriculo-peritoneal, atrial, or pleural shunt placement, and thus, a cholecystic shunt placement was chosen. Due to a history of previous surgeries and comorbidities as well as a large volume of idiopathic and recurrent ascites, open placement was contraindicated in this patient. To the best of our knowledge, we present the first successful adult case of a minimally invasive ventriculo-cholecystic shunt placement under ultrasound and fluoroscopic guidance.

Low-dose IL-2 reduces IL-21+ T cell frequency and induces anti-inflammatory gene expression in type 1 diabetes.

Despite early clinical successes, the mechanisms of action of low-dose interleukin-2 (LD-IL-2) immunotherapy remain only partly understood. Here we examine the effects of interval administration of low-dose recombinant IL-2 (iLD-IL-2) in type 1 diabetes using high-resolution single-cell multiomics and flow cytometry on longitudinally-collected peripheral blood samples. Our results confirm that iLD-IL-2 selectively expands thymic-derived FOXP3+HELIOS+ regulatory T cells and CD56bright NK cells, and show that the treatment reduces the frequency of IL-21-producing CD4+ T cells and of two innate-like mucosal-associated invariant T and Vγ9Vδ2 CD8+ T cell subsets. The cellular changes induced by iLD-IL-2 associate with an anti-inflammatory gene expression signature, which remains detectable in all T and NK cell subsets analysed one month after treatment. These findings warrant investigations into the potential longer-term clinical benefits of iLD-IL-2 in immunotherapy.

The Effect of Immediate Versus Delayed Port Access on 30-Day Infection Rate.

This study compared the 30-day infection risk of chest ports accessed on the same day as placement and chest ports with delayed initial access. The aim was to evaluate a larger data set that provided evidence for the development of port access guidelines. A retrospective chart review of 3322 chest port placement procedures performed between October 15, 2003, and June 10, 2015, was conducted at the interventional radiology department of a single institution. Procedure notes and health records were reviewed to determine time of initial port access, evidence of infection within a 30-day window of port placement, and causal organism(s) of infection. The results demonstrated that 64 ports (1.93%) met infection criteria within 30 days of placement, including 30 of the 945 ports immediately accessed and 34 of the 2377 ports not immediately accessed (3.17% vs 1.43%; P < .005). Dual lumen devices had a statistically significant higher rate of infection compared with single lumen devices (P = .006). This study concluded that there is a statistically significant higher rate of infection if a port is accessed immediately versus when access is deferred to later than 24 hours after placement.

Phenotypic Analysis of Human Lymph Nodes in Subjects With New-Onset Type 1 Diabetes and Healthy Individuals by Flow Cytometry.

Background: Ultrasound guided sampling of human lymph node (LN) combined with advanced flow cytometry allows phenotypic analysis of multiple immune cell subsets. These may provide insights into immune processes and responses to immunotherapies not apparent from analysis of the blood. Methods: Ultrasound guided inguinal LN samples were obtained by both fine needle aspiration (FNA) and core needle biopsy in 10 adults within 8 weeks of diagnosis of type 1 diabetes (T1D) and 12 age-matched healthy controls at two study centers. Peripheral blood mononuclear cells (PBMC) were obtained on the same occasion. Samples were transported same day to the central laboratory and analyzed by multicolour flow cytometry. Results: LN sampling was well-tolerated and yielded sufficient cells for analysis in 95% of cases. We confirmed the segregation of CD69+ cells into LN and the predominance of CD8+ Temra cells in blood previously reported. In addition, we demonstrated clear enrichment of CD8+ naïve, FOXP3+ Treg, class-switched B cells, CD56bright NK cells and plasmacytoid dendritic cells (DC) in LNs as well as CD4+ T cells of the Th2 phenotype and those expressing Helios and Ki67. Conventional NK cells were virtually absent from LNs as were Th22 and Th1Th17 cells. Paired correlation analysis of blood and LN in the same individuals indicated that for many cell subsets, especially those associated with activation: such as CD25+ and proliferating (Ki67+) T cells, activated follicular helper T cells and class-switched B cells, levels in the LN compartment could not be predicted by analysis of blood. We also observed an increase in Th1-like Treg and less proliferating (Ki67+) CD4+ T cells in LN from T1D compared to control LNs, changes which were not reflected in the blood. Conclusions: LN sampling in humans is well-tolerated. We provide the first detailed "roadmap" comparing immune subsets in LN vs. blood emphasizing a role for differentiated effector T cells in the blood and T cell regulation, B cell activation and memory in the LN. For many subsets, frequencies in blood, did not correlate with LN, suggesting that LN sampling would be valuable for monitoring immuno-therapies where these subsets may be impacted.

The DILfrequency study is an adaptive trial to identify optimal IL-2 dosing in patients with type 1 diabetes.

BACKGROUND: Type 1 diabetes (T1D) results from loss of immune regulation, leading to the development of autoimmunity to pancreatic ß cells, involving autoreactive T effector cells (Teffs). Tregs, which prevent autoimmunity, require IL-2 for maintenance of immunosuppressive functions. Using a response-adaptive design, we aimed to determine the optimal regimen of aldesleukin (recombinant human IL-2) to physiologically enhance Tregs while limiting expansion of Teffs. METHODS: DILfrequency is a nonrandomized, open-label, response-adaptive study of participants, aged 18-70 years, with T1D. The initial learning phase allocated 12 participants to 6 different predefined regimens. Then, 3 cohorts of 8 participants were sequentially allocated dose frequencies, based on repeated interim analyses of all accumulated trial data. The coprimary endpoints were percentage change in Tregs and Teffs and CD25 (α subunit of the IL-2 receptor) expression by Tregs, from baseline to steady state. RESULTS: Thirty-eight participants were enrolled, with thirty-six completing treatment. The optimal regimen to maintain a steady-state increase in Tregs of 30% and CD25 expression of 25% without Teff expansion is 0.26 × 106 IU/m2 (95% CI -0.007 to 0.485) every 3 days. Tregs and CD25 were dose-frequency responsive, Teffs were not. The commonest adverse event was injection site reaction (464 of 694 events). CONCLUSIONS: Using a response-adaptive design, aldesleukin treatment can be optimized. Our methodology can generally be employed to immediately access proof of mechanism, thereby leading to more efficient and safe drug development. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number Register, ISRCTN40319192; ClinicalTrials.gov, NCT02265809. FUNDING: Sir Jules Thorn Trust, the Swiss National Science Foundation, Wellcome, JDRF, and NIHR Cambridge Biomedical Research Centre.

Capturing the systemic immune signature of a norovirus infection: an n-of-1 case study within a clinical trial.

BACKGROUND: The infection of a participant with norovirus during the adaptive study of interleukin-2 dose on regulatory T cells in type 1 diabetes (DILT1D) allowed a detailed insight into the cellular and cytokine immune responses to this prevalent gastrointestinal pathogen. METHODS: Serial blood, serum and peripheral blood mononuclear cell (PBMC) samples were collected pre-, and post-development of the infection. To differentiate between the immune response to norovirus and to control for the administration of a single dose of aldesleukin (recombinant interleukin-2, rIL-2) alone, samples from five non-infected participants administered similar doses were analysed in parallel. RESULTS: Norovirus infection was self-limited and resolved within 24 hours, with the subsequent development of anti-norovirus antibodies. Serum pro- and anti-inflammatory cytokine levels, including IL-10, peaked during the symptomatic period of infection, coincident with increased frequencies of monocytes and neutrophils. At the same time, the frequency of regulatory CD4 + T cell (Treg), effector T cell (Teff) CD4 + and CD8 + subsets were dynamically reduced, rebounding to baseline levels or above at the next sampling point 24 hours later.  NK cells and NKT cells transiently increased CD69 expression and classical monocytes expressed increased levels of CD40, HLA-DR and SIGLEC-1, biomarkers of an interferon response. We also observed activation and mobilisation of Teffs, where increased frequencies of CD69 + and Ki-67 + effector memory Teffs were followed by the emergence of memory CD8 + Teff expressing the mucosal tissue homing markers CD103 and ß7 integrin. Treg responses were coincident with the innate cell, Teff and cytokine response. Key Treg molecules FOXP3, CTLA-4, and CD25 were upregulated following infection, alongside an increase in frequency of Tregs with the capacity to home to tissues. CONCLUSIONS: The results illustrate the innate, adaptive and counter-regulatory immune responses to norovirus infection. Low-dose IL-2 administration induces many of the Treg responses observed during infection.

Neonatal and adult recent thymic emigrants produce IL-8 and express complement receptors CR1 and CR2.

The maintenance of peripheral naive T lymphocytes in humans is dependent on their homeostatic division, not continuing emigration from the thymus, which undergoes involution with age. However, postthymic maintenance of naive T cells is still poorly understood. Previously we reported that recent thymic emigrants (RTEs) are contained in CD31+CD25- naive T cells as defined by their levels of signal joint T cell receptor rearrangement excision circles (sjTRECs). Here, by differential gene expression analysis followed by protein expression and functional studies, we define that the naive T cells having divided the least since thymic emigration express complement receptors (CR1 and CR2) known to bind complement C3b- and C3d-decorated microbial products and, following activation, produce IL-8 (CXCL8), a major chemoattractant for neutrophils in bacterial defense. We also observed an IL-8-producing memory T cell subpopulation coexpressing CR1 and CR2 and with a gene expression signature resembling that of RTEs. The functions of CR1 and CR2 on T cells remain to be determined, but we note that CR2 is the receptor for Epstein-Barr virus, which is a cause of T cell lymphomas and a candidate environmental factor in autoimmune disease.

In-depth immunophenotyping data of IL-6R on the human peripheral regulatory T cell (Treg) compartment.

We provide in this paper a detailed characterization of the human peripheral CD4+ CD127lowCD25+ regulatory T cell (Treg) compartment, with a particular emphasis in defining the population expressing higher levels of the IL-6 receptor (IL-6R). We provide a description of the phenotype of this population by assessing both the surface expression by flow cytometry as well as their transcriptional profile and functional features. In addition, we also present functional data describing the responsiveness of these subsets to IL-6 signalling in vitro and to IL-2 in vivo. The data presented in this paper support the research article "Human IL-6RhiTIGIT- CD4+CD127lowCD25+ T cells display potent in vitro suppressive capacity and a distinct Th17 profile" (Ferreira RC et al., 2017; doi: 10.1016/j.clim.2017.03.002) [1].

Computational predictions of the embolus-trapping performance of an IVC filter in patient-specific and idealized IVC geometries.

Embolus transport simulations are performed to investigate the dependence of inferior vena cava (IVC) filter embolus-trapping performance on IVC anatomy. Simulations are performed using a resolved two-way coupled computational fluid dynamics/six-degree-of-freedom approach. Three IVC geometries are studied: a straight-tube IVC, a patient-averaged IVC, and a patient-specific IVC reconstructed from medical imaging data. Additionally, two sizes of spherical emboli (3 and 5 mm in diameter) and two IVC orientations (supine and upright) are considered. The embolus-trapping efficiency of the IVC filter is quantified for each combination of IVC geometry, embolus size, and IVC orientation by performing 2560 individual simulations. The predicted embolus-trapping efficiencies of the IVC filter range from 10 to 100%, and IVC anatomy is found to have a significant influence on the efficiency results ([Formula: see text]). In the upright IVC orientation, greater secondary flow in the patient-specific IVC geometry decreases the filter embolus-trapping efficiency by 22-30 percentage points compared with the efficiencies predicted in the idealized straight-tube or patient-averaged IVCs. In a supine orientation, the embolus-trapping efficiency of the filter in the idealized IVCs decreases by 21-90 percentage points compared with the upright orientation. In contrast, the embolus-trapping efficiency is insensitive to IVC orientation in the patient-specific IVC. In summary, simulations predict that anatomical features of the IVC that are often neglected in the idealized models used for benchtop testing, such as iliac vein compression and anteroposterior curvature, generate secondary flow and mixing in the IVC and influence the embolus-trapping efficiency of IVC filters. Accordingly, inter-subject variability studies and additional embolus transport investigations that consider patient-specific IVC anatomy are recommended for future work.

Glucocorticoid receptor expression in 20 solid tumor types using immunohistochemistry assay.

BACKGROUND: Glucocorticoid receptor (GR) activity plays a role in many aspects of human physiology and may play a crucial role in chemotherapy resistance in a wide variety of solid tumors. A novel immunohistochemistry (IHC) based assay has been previously developed and validated in order to assess GR immunoreactivity in triple-negative breast cancer. The current study investigates the standardized use of this validated assay to assess GR expression in a broad range of solid tumor malignancies. METHODS: Archived formalin-fixed paraffin-embedded tumor bank samples (n=236) from 20 different solid tumor types were analyzed immunohistochemically. Nuclear staining was reported based on the H-score method using differential intensity scores (0, 1+, 2+, or 3+) with the percent stained (out of at least 100 carcinoma cells) recorded at each intensity. RESULTS: GR was expressed in all tumor types that had been evaluated. Renal cell carcinoma, sarcoma, cervical cancer, and melanoma were those with the highest mean H-scores, indicating high levels of GR expression. Colon, endometrial, and gastric cancers had lower GR staining percentages and intensities, resulting in the lowest mean H-scores. CONCLUSION: A validated IHC assay revealed GR immunoreactivity in all solid tumor types studied and allowed for standardized comparison of reactivity among the different malignancies. IMPACT: Baseline expression levels of GR may be a useful biomarker when pharmaceutically targeting GR in research or clinical setting.

Human IL-6RhiTIGIT- CD4+CD127lowCD25+ T cells display potent in vitro suppressive capacity and a distinct Th17 profile.

To date many clinical studies aim to increase the number and/or fitness of CD4+CD127lowCD25+ regulatory T cells (Tregs) in vivo to harness their regulatory potential in the context of treating autoimmune disease. Here, we sought to define the phenotype and function of Tregs expressing the highest levels of IL-6 receptor (IL-6R). We have identified a population of CD4+CD127lowCD25+ TIGIT- T cells distinguished by their elevated IL-6R expression that lacked expression of HELIOS, showed higher CTLA-4 expression, and displayed increased suppressive capacity compared to IL-6RhiTIGIT+ Tregs. IL-6RhiTIGIT- CD127lowCD25+ T cells contained a majority of cells demethylated at FOXP3 and displayed a Th17 transcriptional signature, including RORC (RORγt) and the capacity of producing both pro- and anti-inflammatory cytokines, such as IL-17, IL-22 and IL-10. We propose that in vivo, in the presence of IL-6-associated inflammation, the suppressive function of CD4+CD127lowCD25+ FOXP3+IL-6RhiTIGIT- T cells is temporarily disarmed allowing further activation of the effector functions and potential pathogenic tissue damage.

Development of a Prototype Immunohistochemistry Assay to Measure Programmed Death Ligand-1 Expression in Tumor Tissue.

CONTEXT: - With the abundance of therapeutics targeted against programmed death receptor-1 and its ligand (PD-L1) that are currently approved or in clinical development, there is interest in identifying those patients most likely to respond to these drugs. Expression of PD-L1 may be an indicator of an initial and robust inflammatory response to the presence of tumor cells. Therefore, tumors that express PD-L1 may be the most likely to respond to therapies that interrupt the negative feedback mechanism that leads to PD-L1 upregulation. OBJECTIVE: - To develop a prototype immunohistochemistry assay using the anti-PD-L1 antibody clone 22C3. DESIGN: - The assay was developed and optimized using commercially available reagents and archival tumor-bank tissue. RESULTS: - The optimized immunohistochemistry method had high precision and reproducibility. Using the prototype assay in 142 non-small cell lung cancer and 79 melanoma archival tumor-bank tissue samples, PD-L1 staining was observed at the plasma membrane of nucleated tumor and nontumor cells and, in some cases, as a distinct lichenoid pattern at the tumor-stroma border. Using a preliminary scoring method, 56% (80 of 142) of non-small cell lung cancer and 53% (42 of 79) of melanoma samples were defined as PD-L1+ based on a modified H-score of 1 or more or the presence of a distinctive staining pattern at the tumor-stroma interface. CONCLUSIONS: - The immunohistochemistry assay using the anti-PD-L1 antibody 22C3 merits further investigation in clinical trials and prevalence assessments to further understand the prognostic and predictive value of PD-L1 expression in cancer.

Regulatory T Cell Responses in Participants with Type 1 Diabetes after a Single Dose of Interleukin-2: A Non-Randomised, Open Label, Adaptive Dose-Finding Trial.

BACKGROUND: Interleukin-2 (IL-2) has an essential role in the expansion and function of CD4+ regulatory T cells (Tregs). Tregs reduce tissue damage by limiting the immune response following infection and regulate autoreactive CD4+ effector T cells (Teffs) to prevent autoimmune diseases, such as type 1 diabetes (T1D). Genetic susceptibility to T1D causes alterations in the IL-2 pathway, a finding that supports Tregs as a cellular therapeutic target. Aldesleukin (Proleukin; recombinant human IL-2), which is administered at high doses to activate the immune system in cancer immunotherapy, is now being repositioned to treat inflammatory and autoimmune disorders at lower doses by targeting Tregs. METHODS AND FINDINGS: To define the aldesleukin dose response for Tregs and to find doses that increase Tregs physiologically for treatment of T1D, a statistical and systematic approach was taken by analysing the pharmacokinetics and pharmacodynamics of single doses of subcutaneous aldesleukin in the Adaptive Study of IL-2 Dose on Regulatory T Cells in Type 1 Diabetes (DILT1D), a single centre, non-randomised, open label, adaptive dose-finding trial with 40 adult participants with recently diagnosed T1D. The primary endpoint was the maximum percentage increase in Tregs (defined as CD3+CD4+CD25highCD127low) from the baseline frequency in each participant measured over the 7 d following treatment. There was an initial learning phase with five pairs of participants, each pair receiving one of five pre-assigned single doses from 0.04 × 106 to 1.5 × 106 IU/m2, in order to model the dose-response curve. Results from each participant were then incorporated into interim statistical modelling to target the two doses most likely to induce 10% and 20% increases in Treg frequencies. Primary analysis of the evaluable population (n = 39) found that the optimal doses of aldesleukin to induce 10% and 20% increases in Tregs were 0.101 × 106 IU/m2 (standard error [SE] = 0.078, 95% CI = -0.052, 0.254) and 0.497 × 106 IU/m2 (SE = 0.092, 95% CI = 0.316, 0.678), respectively. On analysis of secondary outcomes, using a highly sensitive IL-2 assay, the observed plasma concentrations of the drug at 90 min exceeded the hypothetical Treg-specific therapeutic window determined in vitro (0.015-0.24 IU/ml), even at the lowest doses (0.040 × 106 and 0.045 × 106 IU/m2) administered. A rapid decrease in Treg frequency in the circulation was observed at 90 min and at day 1, which was dose dependent (mean decrease 11.6%, SE = 2.3%, range 10.0%-48.2%, n = 37), rebounding at day 2 and increasing to frequencies above baseline over 7 d. Teffs, natural killer cells, and eosinophils also responded, with their frequencies rapidly and dose-dependently decreased in the blood, then returning to, or exceeding, pretreatment levels. Furthermore, there was a dose-dependent down modulation of one of the two signalling subunits of the IL-2 receptor, the ß chain (CD122) (mean decrease = 58.0%, SE = 2.8%, range 9.8%-85.5%, n = 33), on Tregs and a reduction in their sensitivity to aldesleukin at 90 min and day 1 and 2 post-treatment. Due to blood volume requirements as well as ethical and practical considerations, the study was limited to adults and to analysis of peripheral blood only. CONCLUSIONS: The DILT1D trial results, most notably the early altered trafficking and desensitisation of Tregs induced by a single ultra-low dose of aldesleukin that resolves within 2-3 d, inform the design of the next trial to determine a repeat dosing regimen aimed at establishing a steady-state Treg frequency increase of 20%-50%, with the eventual goal of preventing T1D. TRIAL REGISTRATION: ISRCTN Registry ISRCTN27852285; ClinicalTrials.gov NCT01827735.

Analysis of the Final DENALI Trial Data: A Prospective, Multicenter Study of the Denali Inferior Vena Cava Filter.

PURPOSE: To report the final 2-year data on the efficacy and safety of a nitinol retrievable inferior vena cava (IVC) filter for protection against pulmonary embolism (PE). MATERIALS AND METHODS: This was a prospective multicenter trial of 200 patients with temporary indications for caval filtration who underwent implantation of the Denali IVC filter. After filter placement, all patients were followed for 2 years after placement or 30 days after filter retrieval. The primary endpoints were technical success of filter implantation in the intended location and clinical success of filter placement and retrieval. Secondary endpoints were incidence of clinically symptomatic recurrent PE, new or propagating deep vein thrombosis (DVT), and filter-related complications including migration, fracture, penetration, and tilt. RESULTS: Filter placement was technically successful in 199 patients (99.5%). Filters were clinically successful in 190 patients (95%). The rate of PE was 3% (n = 6), with 5 patients having a small subsegmental PE and 1 having a lobar PE. New or worsening DVT was noted in 26 patients (13%). Filter retrieval was attempted 125 times in 124 patients and was technically successful in 121 patients (97.6%). The mean filter dwell time at retrieval was 200.8 days (range, 5-736 d). There were no instances of filter fracture, migration, or tilt greater than 15° at the time of filter retrieval or during follow-up. CONCLUSIONS: The Denali IVC filter exhibited high success rates for filter placement and retrieval while maintaining a low complication rate in this clinical trial.

The Importance of Hemorheology and Patient Anatomy on the Hemodynamics in the Inferior Vena Cava.

Inferior vena cava (IVC) filters have been used for nearly half a century to prevent pulmonary embolism in at-risk patients. However, complications with IVC filters remain common. In this study, we investigate the importance of considering the hemorheological and morphological effects on IVC hemodynamics by simulating Newtonian and non-Newtonian blood flow in three IVC models with varying levels of geometric idealization. Partial occlusion by an IVC filter and a thrombus is also considered. More than 99% of the infrarenal IVC volume is found to contain flow in the nonlinear region of the shear rate-viscosity curve for blood (less than 100 s-1) in the unoccluded IVCs. Newtonian simulations performed using the asymptotic viscosity for blood over-predict the non-Newtonian Reynolds numbers by more than a factor of two and under-predict the mean wall shear stress (WSS) by 28-54%. Agreement with the non-Newtonian simulations is better using a characteristic viscosity, but local WSS errors are still large (up to 50%) in the partially occluded cases. Secondary flow patterns in the IVC also depend on the viscosity model and IVC morphological complexity. Non-Newtonian simulations required only a marginal increase in computational expense compared with the Newtonian simulations. We recommend that future studies of IVC hemodynamics consider the effects of hemorheology and IVC morphology when accurate predictions of WSS and secondary flow features are desired.

Development and validation of an immunohistochemistry assay to assess glucocorticoid receptor expression for clinical trials of mifepristone in breast cancer.

BACKGROUND: Glucocorticoid receptor (GR) activity has been associated with chemotherapy resistance and poor outcomes in patients with triple negative breast cancer (TNBC). The aim of this study was to develop an immunohistochemistry (IHC) assay to assess GR expression in archival formalin-fixed, paraffin-embedded human invasive breast carcinoma samples. METHODS: An optimized GR assay protocol was developed using rabbit monoclonal antibody to GR clone D8H2. Precision and reproducibility of the GR IHC assay was determined by conducting multiple staining runs of four invasive breast carcinoma samples using replicate serial sections. Assay sensitivity was examined in 50 TNBC samples (>10 mm) obtained from a tumor bank, and 43 paired TNBC samples from a tissue microarray (TMA) (1.5 mm). GR positivity was assessed using a percent scoring approach with a ≥10% cutoff for nuclear staining of tumor cells at any intensity. Analysis of the paired TMA cores was performed by averaging the scores of the two cores for each case. RESULTS: Equivalent cellular patterns of GR reactivity were observed in all replicates from the multiple staining runs; coefficients of variation did not exceed 4.7% for average H-scores greater than 3.4, thus meeting the criteria for assay precision and reproducibility (coefficient of variation ≤20%). GR expression in TNBC single-tissue samples and TMA cores was characterized as mostly nuclear, with some concurrent cytoplasmic reactivity. Eighty-four percent of the 49 evaluable TNBC samples and 60% of the 42 evaluable paired TMA samples were positive for GR expression. CONCLUSION: A robust and reproducible GR IHC assay was successfully developed for use in invasive breast carcinoma tissues. Differences in GR expression between larger single tissues and smaller TMA cores illustrate the heterogeneity of the disease, as well as potential intra-tumoral heterogeneity. This assay is currently being utilized in clinical trials of mifepristone, a GR antagonist, in patients with TNBC.

Protocol of the adaptive study of IL-2 dose frequency on regulatory T cells in type 1 diabetes (DILfrequency): a mechanistic, non-randomised, repeat dose, open-label, response-adaptive study.

INTRODUCTION: Type 1 diabetes (T1D) is caused by autoimmune destruction of the insulin-producing ß cells in the pancreatic islets, leading to insulinopenia and hyperglycaemia. Genetic analyses indicate that alterations of the interleukin-2 (IL-2) pathway mediating immune activation and tolerance predispose to T1D, specifically the polymorphic expression of the IL-2 receptor-α chain (CD25) on T lymphocytes. Replacement of physiological doses of IL-2 could restore self-tolerance and prevent further autoimmunity by enhancing the function of CD4(+) T regulatory cells (Tregs) to limit the activation of auto reactive T effector cells (Teffs). In this experimental medicine study, we use an adaptive trial design to determine the optimal dosing regimen for IL-2 to improve Treg function while limiting activation of Teffs in participants with T1D. METHODS AND ANALYSIS: The Adaptive study of IL-2 dose frequency on Tregs in type 1 diabetes(DILfrequency) is a mechanistic, non-randomised, repeat dose open-label, response-adaptive study of 36 participants with T1D. The objective is to establish the optimal dose and frequency of ultra-low dose IL-2: to increase Treg frequency within the physiological range, to increase CD25 expression on Tregs, without increasing CD4(+) Teffs. DILfrequency has an initial learning phase where 12 participants are allocated to six different doses and frequencies followed by an interim statistical analysis. After analysis of the learning phase, the Dose and Frequency Committee will select the optimal targets for Treg frequency, Treg CD25 expression and Teff frequency. Three groups of eight participants will be treated consecutively in the confirming phase. Each dose and frequency selected will be based on statistical analysis of all data collected from the previous groups. ETHICS: Ethical approval for DILfrequency was granted on 12 August 2014. RESULTS: The results of this study will be reported, through peer-reviewed journals, conference presentations and an internal organisational report. TRIAL REGISTRATION NUMBERS: NCT02265809, ISRCTN40319192, CRN17571.

Effective recruitment of participants to a phase I study using the internet and publicity releases through charities and patient organisations: analysis of the adaptive study of IL-2 dose on regulatory T cells in type 1 diabetes (DILT1D).

BACKGROUND: A barrier to the successful development of new disease treatments is the timely recruitment of participants to experimental medicine studies that are primarily designed to investigate biological mechanisms rather than evaluate clinical efficacy. The aim of this study was to analyse the performance of three recruitment sources and the effect of publicity events during the Adaptive study of IL-2 dose on regulatory T cells in type 1 diabetes (DILT1D). METHODS: The final study outcome, demography, disease duration, residence and the effect of publicity events on the performance of three recruitment sources (clinics, type 1 diabetes (T1D) disease register and the internet) were analysed from a bespoke DILT1D recruitment database. For the internet source, the origin of website hits in relation to publicity events was also evaluated. RESULTS: A total of 735 potentially eligible participants were approached to identify the final 45 DILT1D participants. A total of 477 (64%) were identified via the disease register, but only 59 (12%) responded to contact. A total of 317 individuals registered with the DILT1D study team. Self-referral via the study website generated 170 (54%) registered individuals and was the most popular and successful source, with 88 (28%) sourced from diabetes clinics and 59 (19%) from the disease register. Of those with known T1D duration (N = 272), the internet and clinics sources identified a larger number (57, 21%) of newly diagnosed T1D (<100 days post-diagnosis) compared to the register (1, 0.4%). The internet extended the geographical reach of the study, enabling both national and international participation. Targeted website posts and promotional events from organisations supporting T1D research and treatment during the trial were essential to the success of the internet recruitment strategy. CONCLUSIONS: Analysis of the DILT1D study recruitment outcomes illustrates the utility of an active internet recruitment strategy, supported by patient groups and charities, funding agencies and sponsors, in successfully conducting an early phase study in T1D. This recruitment strategy should now be evaluated in late-stage trials to develop treatments for T1D and other diseases. TRIAL REGISTRATION: NCT01827735 (registered: 4 April 2013); ISRCTN27852285 (registered: 23 March 2013); DRN767 (registered: 21 January 2013).