Accurate Determination of the Average Rate Constant of Pyrene Excimer Formation for Pyrene-Labeled Macromolecules from the Analysis of Individual Fluorescence Decays with Sums of Exponentials

The average rate constant (⟨k⟩) for pyrene excimer formation (PEF) between an excited and a ground-state pyrenyl label covalently attached to a pyrene-labeled macromolecule (PyLM) has been found to be an ideal parameter to probe macromolecular conformations due to its proportionality to the local concentration ([Py]loc) of pyrenyl labels in PyLM. To date, ⟨k⟩ has only been determined with the model-free analysis (MFA) involving the global analysis of the pyrene monomer and excimer fluorescence decays of PyLM. Unfortunately, the MFA is computationally demanding which prevents its widespread use. To circumvent this complication, a methodology is introduced that involves the analysis of individual fluorescence decays with sums of exponentials (SoE), which are commonly used in the analysis packages of commercial time-resolved fluorometers. The individual fluorescence decays of the pyrene monomer acquired with 286 PyLM were analyzed with a SoE to yield ⟨kSoE-M⟩. The strong correlation between ⟨kSoE-M⟩ and ⟨kMF⟩ obtained from the global MFA indicated that ⟨kSoE-M⟩ was a good representation of ⟨k⟩. Furthermore, the AE-/AE+ ratio, equal to the ratio of the sum of the negative pre-exponential factors over the sum of the positive pre-exponential factors, was determined by fitting the individual pyrene excimer fluorescence decays of the 286 PyLM with a SoE. AE-/AE+ was found to take a value between -1.0 and -0.8, indicating that the pyrenyl labels were not aggregated. This result indicated that [Py]loc was well described by ⟨kSoE-M⟩, so that ⟨kSoE-M⟩ could be used to describe the conformation of macromolecules in the same manner as ⟨kMF⟩. Consequently, the methodology based on the analysis of individual fluorescence decays with sums of exponentials to determine ⟨kSoE-M⟩ and AE-/AE+ provides a robust alternative to the use of the MFA for the study of PyLM to many scientists interested in the characterization of macromolecular conformations.

Medications influencing the risk of fall-related injuries in older adults: case-control and case-crossover design studies

BACKGROUND

Medications influencing the risk of fall-related injuries (FRIs) in older adults have been inconsistent in previous guidelines. This study employed case-control design to assess the association between FRIs and medications, and an additional case-crossover design was conducted to examine the consistency of the associations and the transient effects of the medications on FRIs.

METHODS

This study was conducted using a national claims database (2002-2015) in Korea. Older adults (≥ 65 years) who had their first FRI between 2007 and 2015 were matched with non-cases in 1:2 ratio. Drug exposure was examined for 60 days prior to the date of the first FRI (index date) in the case-control design. The hazard period (1-60 days) and two control periods (121-180 and 181-240 days prior to the index date) were investigated in the case-crossover design. The risk of FRIs with 32 medications was examined using conditional logistic regression after adjusting for other medications that were significant in the univariate analysis. In the case-crossover study, the same conditional model was applied.

RESULTS

In the case-control design, the five medications associated with the highest risk of FRIs were muscle relaxants (adjusted odd ratio(AOR) = 1.35, 95% confidence interval (CI) = 1.31-1.39), anti-Parkinson agents (AOR = 1.30, 95%CI = 1.19-1.40), opioids (AOR = 1.23, 95%CI = 1.19-1.27), antiepileptics (AOR = 1.19, 95%CI = 1.12-1.26), and antipsychotics (AOR = 1.16, 95%CI = 1.06-1.27). In the case-crossover design, the five medications associated with the highest risk of FRIs were angiotensin II antagonists (AOR = 1.87, 95%CI = 1.77-1.97), antipsychotics (AOR = 1.63, 95%CI = 1.42-1.83), anti-Parkinson agents (AOR = 1.58, 95%CI = 1.32-1.85), muscle relaxants (AOR = 1.42, 95%CI = 1.35-1.48), and opioids (AOR = 1.35, 95%CI = 1.30-1.39).

CONCLUSIONS

Anti-Parkinson agents, opioids, antiepileptics, antipsychotics, antidepressants, hypnotics and sedatives, anxiolytics, muscle relaxants, and NSAIDs/antirheumatic agents increased the risk of FRIs in both designs among older adults. Medications with a significant risk only in the case-crossover analysis, such as antithrombotic agents, calcium channel blockers, angiotensin II antagonists, lipid modifying agents, and benign prostatic hypertrophy agents, may have transient effects on FRIs at the time of initiation. Corticosteroids, which were only associated with risk of FRIs in the case-control analysis, had more of cumulative than transient effects on FRIs.

Site-directed mutagenesis of HLA molecules reveals the functional epitope of a human HLA-A1/A36-specific monoclonal antibody

Eplet 44KM is currently listed in the HLA Epitope Registry but does not adhere to the eplet definition of an amino acid configuration within a 3.5 Å radius. Eplet 44KM has been previously redefined to the antibody-verified reactivity pattern 44K/150V/158V, based on reactivity analysis of monoclonal antibody VDK1D12. Since the three residues are always simultaneously present on common HLA alleles, methods to define which residue is crucial for antibody-induction and binding are limited. In this proof-of-concept study, we performed site-directed mutagenesis to narrow down the antibody-verified reactivity pattern 44K/150V/158V to a single amino acid and defined 44K as the eplet or functional epitope of mAb VDK1D12.

Cardiac progenitors instruct second heart field fate through Wnts

The heart develops in a synchronized sequence of proliferation and differentiation of cardiac progenitor cells (CPCs) from two anatomically distinct pools of cells, the first heart field (FHF) and second heart field (SHF). Congenital heart defects arise upon dysregulation of these processes, many of which are restricted to derivatives of the FHF or SHF. Of the conserved set of signaling pathways that regulate development, the Wnt signaling pathway has long been known for its importance in SHF development. The source of such Wnts has remained elusive, though it has been postulated that these Wnts are secreted from ectodermal or endodermal sources. The central question remains unanswered: Where do these Wnts come from? Here, we show that CPCs autoregulate SHF development via Wnt through genetic manipulation of a key Wnt export protein (Wls), scRNA-seq analysis of CPCs, and use of our precardiac organoid system. Through this, we identify dysregulated developmental trajectories of anterior SHF cell fate, leading to a striking single ventricle phenotype in knockout embryos. We then applied our findings to our precardiac organoid model and found that Wnt2 is sufficient to restore SHF cell fate in our model of disrupted endogenous Wnt signaling. In this study, we provide a basis for SHF cell fate decision-proliferation vs. differentiation-autoregulated by CPCs through Wnt.

Multicenter validation of a machine learning phase space electro-mechanical pulse wave analysis to predict elevated left ventricular end diastolic pressure at the point-of-care

BACKGROUND

Phase space is a mechanical systems approach and large-scale data representation of an object in 3-dimensional space. Whether such techniques can be applied to predict left ventricular pressures non-invasively and at the point-of-care is unknown.

OBJECTIVE

This study prospectively validated a phase space machine-learned approach based on a novel electro-mechanical pulse wave method of data collection through orthogonal voltage gradient (OVG) and photoplethysmography (PPG) for the prediction of elevated left ventricular end diastolic pressure (LVEDP).

METHODS

Consecutive outpatients across 15 US-based healthcare centers with symptoms suggestive of coronary artery disease were enrolled at the time of elective cardiac catheterization and underwent OVG and PPG data acquisition immediately prior to angiography with signals paired with LVEDP (IDENTIFY; NCT #03864081). The primary objective was to validate a ML algorithm for prediction of elevated LVEDP using a definition of ≥25 mmHg (study cohort) and normal LVEDP ≤ 12 mmHg (control cohort), using AUC as the measure of diagnostic accuracy. Secondary objectives included performance of the ML predictor in a propensity matched cohort (age and gender) and performance for an elevated LVEDP across a spectrum of comparative LVEDP (<12 through 24 at 1 mmHg increments). Features were extracted from the OVG and PPG datasets and were analyzed using machine-learning approaches.

RESULTS

The study cohort consisted of 684 subjects stratified into three LVEDP categories, ≤12 mmHg (N = 258), LVEDP 13-24 mmHg (N = 347), and LVEDP ≥25 mmHg (N = 79). Testing of the ML predictor demonstrated an AUC of 0.81 (95% CI 0.76-0.86) for the prediction of an elevated LVEDP with a sensitivity of 82% and specificity of 68%, respectively. Among a propensity matched cohort (N = 79) the ML predictor demonstrated a similar result AUC 0.79 (95% CI: 0.72-0.8). Using a constant definition of elevated LVEDP and varying the lower threshold across LVEDP the ML predictor demonstrated and AUC ranging from 0.79-0.82.

CONCLUSION

The phase space ML analysis provides a robust prediction for an elevated LVEDP at the point-of-care. These data suggest a potential role for an OVG and PPG derived electro-mechanical pulse wave strategy to determine if LVEDP is elevated in patients with symptoms suggestive of cardiac disease.

Development and validation of a machine learned algorithm to IDENTIFY functionally significant coronary artery disease

Introduction

Multiple trials have demonstrated broad performance ranges for tests attempting to detect coronary artery disease. The most common test, SPECT, requires capital-intensive equipment, the use of radionuclides, induction of stress, and time off work and/or travel. Presented here are the development and clinical validation of an office-based machine learned algorithm to identify functionally significant coronary artery disease without radiation, expensive equipment or induced patient stress.

Materials and methods

The IDENTIFY trial (NCT03864081) is a prospective, multicenter, non-randomized, selectively blinded, repository study to collect acquired signals paired with subject meta-data, including outcomes, from subjects with symptoms of coronary artery disease. Time synchronized orthogonal voltage gradient and photoplethysmographic signals were collected for 230 seconds from recumbent subjects at rest within seven days of either left heart catheterization or coronary computed tomography angiography. Following machine learning on a proportion of these data (N = 2,522), a final algorithm was selected, along with a pre-specified cut point on the receiver operating characteristic curve for clinical validation. An unseen set of subject signals (N = 965) was used to validate the algorithm.

Results

At the pre-specified cut point, the sensitivity for detecting functionally significant coronary artery disease was 0.73 (95% CI: 0.68–0.78), and the specificity was 0.68 (0.62–0.74). There exists a point on the receiver operating characteristic curve at which the negative predictive value is the same as coronary computed tomographic angiography, 0.99, assuming a disease incidence of 0.04, yielding sensitivity of 0.89 and specificity of 0.42. Selecting a point at which the positive predictive value is maximized, 0.12, yields sensitivity of 0.39 and specificity of 0.88.

Conclusion

The performance of the machine learned algorithm presented here is comparable to common tertiary center testing for coronary artery disease. Employing multiple cut points on the receiver operating characteristic curve can yield the negative predictive value of coronary computed tomographic angiography and a positive predictive value approaching that of myocardial perfusion imaging. As such, a system employing this algorithm may address the need for a non-invasive, no radiation, no stress, front line test, and hence offer significant advantages to the patient, their physician, and healthcare system.

Risk of Fall-Related Injuries Associated with Antidepressant Use in Elderly Patients: A Nationwide Matched Cohort Study

Previous studies have reported a higher risk of falls among tricyclic antidepressant (TCA) users compared to selective serotonin reuptake inhibitor (SSRI) users, yet SSRIs are known as a safer antidepressant class for use in older adults. This study examined the effects of antidepressant use on the risk of fall-related injuries after classifying antidepressant drugs, polypharmacy, and central nervous system (CNS) drugs by therapeutic classes and identifying factors influencing risk of fall-related injuries. A retrospective matched cohort study based on propensity scores was conducted among older adults, aged 70–89 years, who initiated antidepressant use between 1 January 2012 and 31 December 2014 using the national health insurance system senior cohort in Korea. The proportional hazard Cox regression model was used to examine the association between fall-related injuries and antidepressants. The subgroup analyses were performed to assess the risk of fall-related injuries by the number of concurrently administered medications, therapeutic classes of antidepressants, and CNS class medications. This study found that duloxetine, escitalopram, paroxetine, amitriptyline, imipramine, and trazodone significantly increased the risk of fall-related injuries in older adults. When antidepressants were prescribed to older adults, prescribers carefully considered factors including the dose, number of concurrently administered medications, and therapeutic classes of CNS.

Humanization of T cell-mediated immunity in mice

[Figure: see text].

Development of an In Vitro Blink Model for Ophthalmic Drug Delivery

Purpose: The purpose of this study was to develop an advanced in vitro blink model that can be used to examine the release of a wide variety of components (for example, topical ophthalmic drugs, comfort-inducing agents) from soft contact lenses. Methods: The model was designed using computer-aided design software and printed using a stereolithography 3D printer. The eyelid and eyeball were synthesized from polyvinyl alcohol and silicone material, respectively. Simulated tear fluid was infused through tubing attached to the eyelid using a syringe pump. With each blink cycle, the eyelid slides and flexes across the eyeball to create an artificial tear film layer. The flow-through fluid was collected using a specialized trough. Two contact lenses, etafilcon A and senofilcon A, were incubated in 2 mL of a water-soluble red dye for 24 h and then placed on the eye model (n = 3). The release of the dye was measured over 24 h using a tear flow rate of 5 µL/min. Results: Approximately 25% of the fluid that flowed over the eye model was lost due to evaporation, nonspecific absorption, and residual dead volume. Senofilcon A absorbed more dye (47.6 ± 2.7 µL) than etafilcon A (22.3 ± 2.0 µL). For etafilcon A, the release of the dye followed a burst-plateau profile in the vial but was sustained in the eye model. For senofilcon A, the release of the dye was sustained in both the vial and the eye model, though more dye was released in the vial (p < 0.05). Overall, the release of the dye from the contact lenses was higher in the vial compared with the eye model (p < 0.05). Conclusion: The blink model developed in this study could be used to measure the release of topical ophthalmic drugs or comfort agents from contact lenses. Simulation of a blink mechanism, an artificial tear film, and nonspecific absorption in an eye model may provide better results than a simple, static vial incubation model.

Use of budget savings from patent expiration of cancer drugs to improve affordability and accessibility

BACKGROUND

The introduction of generics after the loss of patent exclusivity plays a major role in budget savings by significantly decreasing drug prices. The aims of this study were to estimate the budget savings from off-patent cancer drugs in 2020-2024 and to inform decision makers on how these savings could be used to improve the affordability of innovative cancer treatments in South Korea.

METHODS

A model was developed to calculate budget savings from off-patent cancer drug use in Korea over 5 years (2020-2024). Cancer drugs with one or more valid patents that expire between 2020 and 2024 in Korea were selected. Key input parameters in the model included market share of generics, market growth, and prices of originators and generics. To reflect market dynamics after patent expiration, the trends of the off-patent market were estimated using historical sales volume data of IQVIA from 2012 to 2018. The study assumed that the prices of off-patent drugs decreased according to the price regulations set by the Korean government and that the off-patent market sales volume did not grow. Sensitivity analyses were performed to investigate the uncertainty in model input parameters.

RESULTS

A total of 24 cancer drugs which met selection criteria were identified. In the base case analysis, patent expiration of cancer drugs between 2020 and 2024 could lead to a spending reduction of ₩234,429 million ($203 million), which was 20% of the cancer drug expenditure in the 5-year period. The savings ranged from ₩157,633 million ($136 million) to ₩434,523 million ($376 million) depending on the scenarios in sensitivity analyses.

CONCLUSIONS

The findings indicate that patent loss of cancer drugs could lead to a 20% reduction in spending on cancer drugs over the next 5 years in South Korea. The savings could be used to improve the affordability of innovative, advanced cancer drugs for 94,000 cancer patients by reallocating the budget savings from patent expiration.

Evaluation of seafood traceability system in Korea: demand-oriented analysis

The Korean government tried to secure food safety by revitalization of seafood traceability system since there has been growing dissatisfaction toward of food system related to seafood in Korea. This study examines the consumers’ perspective on seafood traceability system and the value of seafood traceability in Korea using contingent valuation method. The model includes preference and recognition of respondents for the seafood traceability system, and socio-demographic characteristics. The result of the model shows that respondents think positively about seafood traceability system and it is expected that approximately $44.94 million can be generated annually from the seafood traceability system. The result implies that it is necessary to promote the system in order to make this system known, the benefit of which is helpful in food safety.

The risk of vancomycin toxicity in patients with liver impairment

BACKGROUND

The influence of liver disease on the pharmacokinetic profile, the risk of acute kidney injury, and excessive drug exposure in patients treated with vancomycin was examined.

METHODS

A retrospective cohort study was performed with patients discharged from a medical center between January 2011 and June 2018 who received vancomycin therapy. Patients were stratified according to liver dysfunction (no to mild liver dysfunction (NMLD) and moderate to severe liver dysfunction (MSLD) based on the Child-Pugh score. The risk of acute kidney injury was compared between patients who were stratified by the attainment of a target serum trough concentration (10 mg/dL to 20 mg/dL) and the vancomycin ratio formed between the area under the curve and minimum inhibitory concentration. The impact of liver dysfunction and a daily dose of vancomycin on the risk of acute kidney injury and vancomycin AUC:MIC > 600 were tested using logistic regression with and without adjusting for the study variables.

RESULTS

A total of 408 patients empirically treated with vancomycin were included in this study (237 with NMLD and 171 with MSLD). Mean vancomycin trough concentrations (17.5 ± 8.4 mg/dL versus 15.3 ± 5.2 mg/dL, p = 0.0049) and AUC:MIC ratios (549.4 ± 217.2 versus 497.5 ± 117.3, 0.0065) were significantly higher in the MSLD group when compared to the NMLD group, respectively. Vancomycin clearance was also lower in the MSLD group and corresponded to a longer half-life. The proportion of patients who developed acute kidney injury was greater in patients with MSLD when compared to NMLD (7.6% versus 3.8%, respectively; p = 0.0932); however, the difference was statistically insignificant. Furthermore, supratherapeutic serum trough concentrations and AUC:MIC ratios were more common in the MSLD group versus the NMLD group (27.5% versus 13.9%, p = 0.0007 and 28.7% versus 17.3%, respectively; p = 0.0063).

CONCLUSIONS

MSLD correlates with an increased risk of supratherapeutic vancomycin exposure. Although patients with MSLD had a higher risk of acute kidney injury, the difference was not significant.

Optogenetic intervention of seizures improves spatial memory in a mouse model of chronic temporal lobe epilepsy

OBJECTIVE

To determine if closed-loop optogenetic seizure intervention, previously shown to reduce seizure duration in a well-established mouse model chronic temporal lobe epilepsy (TLE), also improves the associated comorbidity of impaired spatial memory.

METHODS

Mice with chronic, spontaneous seizures in the unilateral intrahippocampal kainic acid model of TLE, expressing channelrhodopsin in parvalbumin-expressing interneurons, were implanted with optical fibers and electrodes, and tested for response to closed-loop light intervention of seizures. Animals that responded to closed-loop optogenetic curtailment of seizures were tested in the object location memory test and then given closed-loop optogenetic intervention on all detected seizures for 2 weeks. Following this, they were tested with a second object location memory test, with different objects and contexts than used previously, to assess if seizure suppression can improve deficits in spatial memory.

RESULTS

Animals that received closed-loop optogenetic intervention performed significantly better in the second object location memory test compared to the first test. Epileptic controls with no intervention showed stable frequency and duration of seizures, as well as stable spatial memory deficits, for several months after the precipitating insult.

SIGNIFICANCE

Many currently available treatments for epilepsy target seizures but not the associated comorbidities, therefore there is a need to investigate new potential therapies that may be able to improve both seizure burden and associated comorbidities of epilepsy. In this study, we showed that optogenetic intervention may be able to both shorten seizure duration and improve cognitive outcomes of spatial memory.

Budget Impact of Switching to Biosimilar Trastuzumab (CT-P6) for the Treatment of Breast Cancer and Gastric Cancer in 28 European Countries

BACKGROUND

As the economic burden of treating cancer patients has been soaring in European countries, performing a budget impact analysis is becoming one of the requirements for payers' application dossiers.

OBJECTIVE

The objective of this study was to estimate the budgetary impact of introducing the biosimilar trastuzumab (CT-P6) from the payer's perspective and to determine the number of additional patients who could be treated with resulting savings in 28 European countries.

METHODS

A budget impact model was developed to analyze the financial impact of switching from originator trastuzumab to biosimilar CT-P6 in the treatment of early and metastatic breast cancer and metastatic gastric cancer with a time horizon of 1-5 years. Budgetary savings and the number of patients potentially affected were measured based on epidemiological and sales volume data. The base-case analysis assumed that the price of CT-P6 is 70% of the originator price, the switching rate of originator to CT-P6 in the first year is 20%, and the annual growth in the switching rate for each subsequent year is 5%.

RESULTS

For analyses using the base-case scenario following CT-P6 introduction, the total estimated budgetary savings over a 5-year period (depending on the scenario) ranged from €1.13 billion to €2.27 billion based on epidemiological data, or from €0.91 billion to €1.82 billion based on sales volume data. In the first year only, the projected budgetary savings ranged from €58 million to €136 million, and the number of additional patients who could be treated using the savings ranged from 3503 to 7078 by sensitivity analysis.

CONCLUSIONS

The conducted budget impact analysis assessing a switch from originator trastuzumab to biosimilar CT-P6 in 28 European countries indicates that budget savings could be between €0.91 billion and €2.27 billion over the next 5 years. These savings could be used to help improve patient access to local biologics in their respective countries while simultaneously strengthening the overall public health landscape across the European Union.

STIM1 and STIM2 Mediate Cancer-Induced Inflammation in T Cell Acute Lymphoblastic Leukemia

T cell acute lymphoblastic leukemia (T-ALL) is commonly associated with activating mutations in the NOTCH1 pathway. Recent reports have shown a link between NOTCH1 signaling and intracellular Ca²⁺ homeostasis in T-ALL. Here, we investigate the role of store-operated Ca²⁺ entry (SOCE) mediated by the Ca²⁺ channel ORAI1 and its activators STIM1 and STIM2 in T-ALL. Deletion of STIM1 and STIM2 in leukemic cells abolishes SOCE and significantly prolongs the survival of mice in a NOTCH1-dependent model of T-ALL. The survival advantage is unrelated to the leukemic cell burden but is associated with the SOCE-dependent ability of malignant T lymphoblasts to cause inflammation in leukemia-infiltrated organs. Mice with STIM1/STIM2-deficient T-ALL show a markedly reduced necroinflammatory response in leukemia-infiltrated organs and downregulation of signaling pathways previously linked to cancer-induced inflammation. Our study shows that leukemic T lymphoblasts cause inflammation of leukemia-infiltrated organs that is dependent on SOCE.

T cell acute lymphoblastic leukemia (T-ALL) is an aggressive cancer of T cell progenitors affecting children and adults. Saint Fleur-Lominy et al. show that calcium influx mediated by STIM1 and STIM2 promotes the proinflammatory function of leukemic cells and premature death from leukemia.

Treatment Costs and Factors Associated with Glycemic Control among Patients with Diabetes in the United Arab Emirates

Background

We aimed to estimate the proportion of patients with diabetes who achieved target glycemic control, to estimate diabetes-related costs attributable to poor control, and to identify factors associated with them in the United Arab Emirates.

Methods

This retrospective cohort study used administrative claims data handled by Abu Dhabi Health Authority (January 2010 to June 2012) to determine glycemic control and diabetes-related treatment costs. A total of 4,058 patients were matched using propensity scores to eliminate selection bias between patients with glycosylated hemoglobin (HbA1c) <7% and HbA1c ≥7%. Diabetes-related costs attributable to poor control were estimated using a recycled prediction method. Factors associated with glycemic control were investigated using logistic regression and factors associated with these costs were identified using a generalized linear model.

Results

During the 1-year follow-up period, 46.6% of the patients achieved HbA1c <7%. Older age, female sex, better insurance coverage, non-use of insulin in the index diagnosis month, and non-use of antidiabetic medications during the follow-up period were significantly associated with improved glycemic control. The mean diabetes-related annual costs were $2,282 and $2,667 for patients with and without glycemic control, respectively, and the cost attributable to poor glycemic control was $172 (95% confidence interval [CI], $164–180). The diabetes-related costs were lower with mean HbA1c levels <7% (cost ratio, 0.94; 95% CI, 0.88–0.99). The costs were significantly higher in patients aged ≥65 years than those aged ≤44 years (cost ratio, 1.45; 95% CI, 1.25–1.70).

Conclusion

More than 50% of patients with diabetes had poorly controlled HbA1c. Poor glycemic control may increase diabetes-related costs.

The risk of cardiac events in patients who received concomitant levofloxacin and amiodarone

OBJECTIVES

Levofloxacin and amiodarone are both known to prolong the QT interval. This study was conducted to estimate the risk of cardiac events in patients receiving concomitant levofloxacin and amiodarone.

METHODS

The study included patients who were admitted to a large academic community medical center from 1/2012 to 12/2015 and received both levofloxacin and amiodarone at some point during their hospitalization. Patients received concomitant or non-concomitant levofloxacin and amiodarone during hospitalization. The primary outcome was the occurrence of cardiac events during therapy. The secondary outcome was the proportion of patients with an electrocardiogram performed before and after initiation of therapy. Odds ratios for cardiac events were calculated using a multivariable logistic regression model with and without adjusting for the study variables. The concomitant group was further evaluated for predictors of the primary outcome using multivariable logistic regression.

RESULTS

This study included 240 patients, 164 (68.3%) of whom received concomitant levofloxacin and amiodarone. Concomitant medication therapy was associated with a greater than six-fold increased risk of cardiac events after adjusting for the study variables (Odds Ratio=6.20; 95% Confidence Interval=1.34-28.62).

CONCLUSIONS

Patients receiving concomitant amiodarone and levofloxacin experienced a five-fold increase in cardiac events compared to patients given either medication alone.

The association of socioeconomic and clinical characteristics with health-related quality of life in patients with psoriasis: a cross-sectional study

BACKGROUND

This study aimed to determine the socioeconomic and clinical characteristics affecting health-related quality of life (HRQoL) in patients with psoriasis.

METHODS

A cross-sectional study was conducted between March and June 2015 using data obtained via an Internet-based survey completed by a psoriasis patient group in Korea. The survey included items regarding demographic, socioeconomic, and clinical characteristics and HRQoL. Patients' HRQoL impairment was classified as severe if their Dermatology Life Quality Index Scores were ≥ 11. Factors influencing HRQoL impairment were identified using multivariate logistic regression analysis.

RESULTS

Of the 299 respondents, 161 (53.8%) exhibited severe HRQoL impairment. The Dermatology Life Quality Index scores were significantly associated with gender, annual income, neck psoriasis, psoriasis-related resignation from work, and use of oral and herbal medications. The severity of HRQoL impairment in women was twice that observed in men (odds ratio [OR] = 2.00, 95% confidence interval (CI): 1.05-3.80). Patients with psoriasis on the neck exhibited significantly greater HRQoL impairment than those with psoriasis on other areas of their bodies (OR = 2.30, 95% CI: 1.20-4.43). With respect to the socioeconomic status, patients who earned > 40 million KRW (approximately 34,000 USD; high-income group) showed less HRQoL impairment compared with those who had lower incomes (OR = 0.47, 95% CI: 0.28-0.80). Patients with severe HRQoL impairment used oral (OR = 2.04, 95% CI: 1.20-3.44) and herbal (OR = 1.86, 95% CI: 1.04-3.34) medications more often relative to patients with less severe HRQoL impairment.

CONCLUSIONS

HRQoL in patients with psoriasis was significantly associated with their demographic and socioeconomic characteristics and employment status. The presence of psoriasis on exposed areas of the body was significantly associated with patients' HRQoL and employment status. Further research is required to evaluate the impact of psoriasis on patients' productivity.

Impact of warfarin discharge education program on hospital readmission and treatment costs

Background Although warfarin is highly effective, management of patients prescribed warfarin is complex due to its narrow therapeutic window. Objective To evaluate the impact of a formal warfarin discharge education program (WDEP) on hospital readmission and treatment costs in patients who received warfarin therapy. Setting Robert Wood Johnson University Hospital Somerset in Somerville, New Jersey, USA. Method In this interventional cohort study, patients were assigned to either the WDEP group or the usual care group. The effects of the WDEP on readmission within 90 days after discharge were analyzed using Cox proportional hazards models. Factors influencing treatment cost were identified using generalized linear model with log-link function and gamma distribution. Main outcome measure Hospital readmission within 90 days and treatment costs associated with hospital readmission. Results Among 692 eligible patients, 203 in each group were matched using propensity scores and there were no statistically significant differences in the patient baseline characteristics between two groups. The risk of all-cause readmission within 90 days was significantly lower in the WDEP group compared to the usual care group (relative risk = 0.46, 95% CI 0.28-0.76). The treatment costs associated with hospital readmission in the WDEP group were 19% lower than those in the usual care group after adjusting for the study variables. Conclusion A formal, individualized WDEP provided by pharmacists resulted in significant reduction of readmission and treatment costs. The economic burden of treatment costs associated with warfarin can be controlled if well-organized warfarin education is provided to patients who received warfarin therapy.

Incremental Treatment Costs Attributable to Overweight and Obesity in Patients with Diabetes: Quantile Regression Approach

OBJECTIVE

This study aimed to estimate treatment costs attributable to overweight and obesity in patients with diabetes who were less than 65 years of age in the United States.

METHODS

This study used data from the Medical Expenditure Panel Survey from 2001 to 2013. Patients with diabetes were identified by using the International Classification of Diseases, Ninth Revision, Clinical Modification code (250), clinical classification codes (049 and 050), or self-reported physician diagnoses. Total treatment costs attributable to overweight and obesity were calculated as the differences in the adjusted costs compared with individuals with diabetes and normal weight. Adjusted costs were estimated by using generalized linear models or unconditional quantile regression models.

RESULTS

The mean annual treatment costs attributable to obesity were $1,852 higher than those attributable to normal weight, while costs attributable to overweight were $133 higher. The unconditional quantile regression results indicated that the impact of obesity on total treatment costs gradually became more significant as treatment costs approached the upper quantile.

CONCLUSIONS

Among patients with diabetes who were less than 65 years of age, patients with diabetes and obesity have significantly higher treatment costs than patients with diabetes and normal weight. The economic burden of diabetes to society will continue to increase unless more proactive preventive measures are taken to effectively treat patients with overweight or obesity.

A veritable menagerie of heritable bacteria from ants, butterflies, and beyond: broad molecular surveys and a systematic review

Maternally transmitted bacteria have been important players in the evolution of insects and other arthropods, affecting their nutrition, defense, development, and reproduction. Wolbachia are the best studied among these and typically the most prevalent. While several other bacteria have independently evolved a heritable lifestyle, less is known about their host ranges. Moreover, most groups of insects have not had their heritable microflora systematically surveyed across a broad range of their taxonomic diversity. To help remedy these shortcomings we used diagnostic PCR to screen for five groups of heritable symbionts-Arsenophonus spp., Cardinium hertigii, Hamiltonella defensa, Spiroplasma spp., and Wolbachia spp.-across the ants and lepidopterans (focusing, in the latter case, on two butterfly families-the Lycaenidae and Nymphalidae). We did not detect Cardinium or Hamiltonella in any host. Wolbachia were the most widespread, while Spiroplasma (ants and lepidopterans) and Arsenophonus (ants only) were present at low levels. Co-infections with different Wolbachia strains appeared especially common in ants and less so in lepidopterans. While no additional facultative heritable symbionts were found among ants using universal bacterial primers, microbes related to heritable enteric bacteria were detected in several hosts. In summary, our findings show that Wolbachia are the dominant heritable symbionts of ants and at least some lepidopterans. However, a systematic review of symbiont frequencies across host taxa revealed that this is not always the case across other arthropods. Furthermore, comparisons of symbiont frequencies revealed that the prevalence of Wolbachia and other heritable symbionts varies substantially across lower-level arthropod taxa. We discuss the correlates, potential causes, and implications of these patterns, providing hypotheses on host attributes that may shape the distributions of these influential bacteria.

Trastuzumab for the treatment of HER2-positive metastatic adenocarcinoma of the stomach or gastro-oesophageal junction

This paper presents a summary of the evidence review group (ERG) report into trastuzumab for the treatment of human epidermal growth factor receptor 2 (HER2)-positive metastatic adenocarcinoma of the stomach (mGC) or gastro-oesophageal junction. HER2 positivity is defined by immunohistochemistry (IHC)3+ or IHC2+/fluorescence in situ hybridisation (FISH)+. The decision problem addressed was the testing of the whole mGC population with IHC and, for IHC2+ patients, also with FISH, followed by treatment of HER2-positive patients with trastuzumab combined with cisplatin and either capecitabine or 5-fluorouracil (5-FU) [HCX (trastuzumab, cisplatin, capecitabine)/fluorouracil (F)] compared with current standard NHS therapy. The manufacturer's submission contained direct evidence from the ToGA trial, a well-conducted, multinational, phase III randomised controlled trial (RCT) that compared HCX/F with cisplatin and a fluoropyrimidine alone [cisplatin, capecitabine (CX)/F]. HCX/F showed statistically significantly better overall survival in the European Medicines Agency-licensed population subgroup (74%) (hazard ratio 0.65, 95% confidence interval 0.51 to 0.83), corresponding to median survival of 16 months versus 11.8 months. No other evidence exists for the efficacy of any therapy in a known HER2-positive mGC population; other comparisons extrapolate from trials in mixed HER2 status populations. The ERG accepted the manufacturer's view that a meaningful network meta-analysis to establish a comparison for HCX/F compared with current standard NHS therapy [epirubicin, cisplatin, capecitabine (ECX)/epirubicin, oxaliplatin, capecitabine (EOX)/epirubicin, cisplatin, 5-FU (ECF)] was not possible, but was unconvinced by arguments advanced in the alternative narrative synthesis. These involved disregarding evidence from a meta-analysis and interpreting non-significant results of small RCTs comparing epirubicin-containing triplets with cisplatin, 5-FU (CF)/capecitabine (X) doublets as evidence of no difference between triplet and doublet regimens. The high CX/F dose in the ToGA trial was an additional basis for the contention of equivalence. An appropriate de novo economic evaluation, including an economic model that separately compared HCX or trastuzumab, cisplatin, 5-FU (HCF) with the triplet regimens ECX, EOX and ECF, based on a simple, three-state cohort model (progression-free, disease, progression and death), was submitted. Utility weights were applied to estimate quality-adjusted life-years (QALYs). Costs were assessed from an NHS perspective, and incorporated the acquisition and monitoring costs of the alternative regimens, HER2 testing, adverse events and other supportive care costs. An 8-year time horizon was used to represent a lifetime analysis. Results from the ToGA trial were combined with a series of assumptions on relative treatment effects and testing strategies. The manufacturer's results produced an incremental cost-effectiveness ratio (ICER) of £ 53,010 per QALY for HCX versus ECX. Although the manufacturer undertook a detailed set of sensitivity analyses, several alternative model assumptions were not evaluated. The ERG undertook a series of alternative base-case analyses. As a result of these analyses, EOX replaced ECX as the appropriate comparator, and the ICER for the comparison of HCX vs EOX increased to between £ 66,982 and £ 71,636 per QALY. The impact of implementation of alternative testing strategies remained unclear. There is also considerable uncertainty surrounding the true estimate of effectiveness for the comparison between triplet regimens containing epirubicin (ECX/ECF/EOX) and doublet CX/F regimens. Consequently, the view of the ERG was that there is insufficient evidence on the efficacy of HCX/F compared with current NHS standard therapy for an ICER to be determined with any degree of certainty.

Ceacam1 separates graft-versus-host-disease from graft-versus-tumor activity after experimental allogeneic bone marrow transplantation

Background

Allogeneic bone marrow transplantation (allo-BMT) is a potentially curative therapy for a variety of hematologic diseases, but benefits, including graft-versus-tumor (GVT) activity are limited by graft-versus-host-disease (GVHD). Carcinoembryonic antigen related cell adhesion molecule 1 (Ceacam1) is a transmembrane glycoprotein found on epithelium, T cells, and many tumors. It regulates a variety of physiologic and pathological processes such as tumor biology, leukocyte activation, and energy homeostasis. Previous studies suggest that Ceacam1 negatively regulates inflammation in inflammatory bowel disease models.

Methods

We studied Ceacam1 as a regulator of GVHD and GVT after allogeneic bone marrow transplantation (allo-BMT) in mouse models. In vivo, Ceacam1^−/− T cells caused increased GVHD mortality and GVHD of the colon, and greater numbers of donor T cells were positive for activation markers (CD25^hi, CD62L^lo). Additionally, Ceacam1^−/− CD8 T cells had greater expression of the gut-trafficking integrin α₄β₇, though both CD4 and CD8 T cells were found increased numbers in the gut post-transplant. Ceacam1^−/− recipients also experienced increased GVHD mortality and GVHD of the colon, and alloreactive T cells displayed increased activation. Additionally, Ceacam1^−/− mice had increased mortality and decreased numbers of regenerating small intestinal crypts upon radiation exposure. Conversely, Ceacam1-overexpressing T cells caused attenuated target-organ and systemic GVHD, which correlated with decreased donor T cell numbers in target tissues, and mortality. Finally, graft-versus-tumor survival in a Ceacam1⁺ lymphoma model was improved in animals receiving Ceacam1^−/− vs. control T cells.

Conclusions

We conclude that Ceacam1 regulates T cell activation, GVHD target organ damage, and numbers of donor T cells in lymphoid organs and GVHD target tissues. In recipients of allo-BMT, Ceacam1 may also regulate tissue radiosensitivity. Because of its expression on both the donor graft and host tissues, this suggests that targeting Ceacam1 may represent a potent strategy for the regulation of GVHD and GVT after allogeneic transplantation.

Trastuzumab for the treatment of HER2- positive metastatic adenocarcinoma of the stomach or gastro-oesophageal junction

This paper presents a summary of the evidence review group (ERG) report into trastuzumab for the treatment of human epidermal growth factor receptor 2 (HER2)-positive metastatic adenocarcinoma of the stomach (mGC) or gastro-oesophageal junction. HER2 positivity is defined by immunohistochemistry (IHC)3+ or IHC2+/fluorescence in situ hybridisation (FISH)+. The decision problem addressed was the testing of the whole mGC population with IHC and, for IHC2+ patients, also with FISH, followed by treatment of HER2-positive patients with trastuzumab combined with cisplatin and either capecitabine or 5-fluorouracil (5-FU) [HCX (trastuzumab, cisplatin, capecitabine)/fluorouracil (F)] compared with current standard NHS therapy. The manufacturer’s submission contained direct evidence from the ToGA trial, a well-conducted, multinational, phase III randomised controlled trial (RCT) that compared HCX/F with cisplatin and a fluoropyrimidine alone [cisplatin, capecitabine (CX)/F]. HCX/F showed statistically significantly better overall survival in the European Medicines Agency-licensed population subgroup (74%) (hazard ratio 0.65, 95% confidence interval 0.51 to 0.83), corresponding to median survival of 16 months versus 11.8 months. No other evidence exists for the efficacy of any therapy in a known HER2-positive mGC population; other comparisons extrapolate from trials in mixed HER2 status populations. The ERG accepted the manufacturer’s view that a meaningful network meta-analysis to establish a comparison for HCX/F compared with current standard NHS therapy [epirubicin, cisplatin, capecitabine (ECX)/epirubicin, oxaliplatin, capecitabine (EOX)/epirubicin, cisplatin, 5-FU (ECF)] was not possible, but was unconvinced by arguments advanced in the alternative narrative synthesis. These involved disregarding evidence from a meta-analysis and interpreting non-significant results of small RCTs comparing epirubicin-containing triplets with cisplatin, 5-FU (CF)/capecitabine (X) doublets as evidence of no difference between triplet and doublet regimens. The high CX/F dose in the ToGA trial was an additional basis for the contention of equivalence. An appropriate de novo economic evaluation, including an economic model that separately compared HCX or trastuzumab, cisplatin, 5-FU (HCF) with the triplet regimens ECX, EOX and ECF, based on a simple, three-state cohort model (progression-free, disease, progression and death), was submitted. Utility weights were applied to estimate quality-adjusted life-years (QALYs). Costs were assessed from an NHS perspective, and incorporated the acquisition and monitoring costs of the alternative regimens, HER2 testing, adverse events and other supportive care costs. An 8-year time horizon was used to represent a lifetime analysis. Results from the ToGA trial were combined with a series of assumptions on relative treatment effects and testing strategies. The manufacturer’s results produced an incremental cost-effectiveness ratio (ICER) of £53,010 per QALY for HCX versus ECX. Although the manufacturer undertook a detailed set of sensitivity analyses, several alternative model assumptions were not evaluated. The ERG undertook a series of alternative base-case analyses. As a result of these analyses, EOX replaced ECX as the appropriate comparator, and the ICER for the comparison of HCX vs EOX increased to between £66,982 and £71,636 per QALY. The impact of implementation of alternative testing strategies remained unclear. There is also considerable uncertainty surrounding the true estimate of effectiveness for the comparison between triplet regimens containing epirubicin (ECX/ECF/EOX) and doublet CX/F regimens. Consequently, the view of the ERG was that there is insufficient evidence on the efficacy of HCX/F compared with current NHS standard therapy for an ICER to be determined with any degree of certainty.

Capecitabine for the treatment of advanced gastric cancer

This paper presents a summary of the evidence review group (ERG) report into capecitabine for advanced gastric cancer (aGC). Capecitabine is an oral prodrug of 5-fluorouracil (5-FU). The decision problem addressed was the use of capecitabine (X) compared to 5-FU (F), in combination regimens with platinum agents [cisplatin (C) or oxaliplatin (O)] with or without epirubicin (E), in patients with inoperable aGC. Approximately 7000 new cases of gastric cancer are diagnosed in England and Wales every year. Of these, 80% are candidates for palliative chemotherapy and around 2900 receive such treatment. The standard UK practice for patients with aGC who are considered fit enough has consisted of a triplet regimen comprising intravenous 5-FU in combination with a platinum agent (capecitabine or oxaliplatin) and epirubicin. The manufacturer's submission (MS) focused on direct evidence from two phase III non-inferiority randomised controlled trials (RCTs), REAL-2 (Randomized ECF for Advanced and Locally advanced oesophagogastric cancer-2; n = 1002) and ML17032 (n = 316). REAL-2 randomised patients to four regimens (ECF, ECX, EOF and EOX) to compare 5-FU with capecitabine and cisplatin with oxaliplatin, whereas ML17032 compared CX with CF. Efficacy outcomes from these trials were pooled in an individual patient data (IPD) meta-analysis. Both RCTs demonstrated statistically significant non-inferiority of capecitabine on the outcome of overall survival (OS) assessed in the per-protocol population; equivalent results were also demonstrated for progression-free survival (PFS). The IPD meta-analysis found a statistically significant benefit in OS for capecitabine compared with 5-FU [unadjusted hazard ratio (HR): 0.87; 95% confidence interval (CI) 0.77 to 0.98, p = 0.027]. There was no evidence of a poorer safety profile for capecitabine overall, nor of any difference in quality of life (QoL) between the two fluoropyrimidines. The MS included a de novo economic evaluation based on a cost-minimisation analysis (CMA), where the costs of capecitabine-based regimens were compared with their equivalent 5-FU-based regimens in aGC. A time horizon of 5.5 cycles (each lasting for 21 days) was used in the base-case analysis, representing the duration of treatment. The results of the manufacturer's base-case analysis showed that capecitabine regimens are associated with mean net cost savings of 1620 pounds (ECX vs ECF), 1572 pounds (EOX vs EOF) and 4210 pounds (CX vs CF). The manufacturer failed to comment explicitly on the uncertainty around the estimates of efficacy and on the fact that the IPD meta-analysis suggests that capecitabine may actually be more effective on average. Further analyses exploring additional costs incurred by the UK NHS from extending survival duration showed that these are unlikely to have a material effect on conclusions. A full probabilistic analysis was not performed; however, the evidence explored by the MS and ERG is consistent in suggesting that capecitabine has a lower mean cost than 5-FU-based regimens. The submission was considered to contain convincing evidence of the non-inferiority of capecitabine to 5-FU on survival; this evidence was considered to be applicable to UK practice. Although some uncertainty remains, the ERG deemed CMA to be an appropriate framework with which to analyse this decision problem. Overall cost estimates for the CMA were generated appropriately and were robust to uncertainties regarding assumptions and sources. At the time of writing, the guidance document issued by NICE on 28 July 2010 states that capecitabine in combination with a platinum-based regimen is recommended for the first-line treatment of inoperable advanced gastric cancer.

Capecitabine for the treatment of advanced gastric cancer

This paper presents a summary of the evidence review group (ERG) report into capecitabine for advanced gastric cancer (aGC). Capecitabine is an oral prodrug of 5-fluorouracil (5-FU). The decision problem addressed was the use of capecitabine (X) compared to 5-FU (F), in combination regimens with platinum agents [cisplatin (C) or oxaliplatin (O)] with or without epirubicin (E), in patients with inoperable aGC. Approximately 7000 new cases of gastric cancer are diagnosed in England and Wales every year. Of these, 80% are candidates for palliative chemotherapy and around 2900 receive such treatment. The standard UK practice for patients with aGC who are considered fit enough has consisted of a triplet regimen comprising intravenous 5-FU in combination with a platinum agent (capecitabine or oxaliplatin) and epirubicin. The manufacturer’s submission (MS) focused on direct evidence from two phase III non-inferiority randomised controlled trials (RCTs), REAL-2 (Randomized ECF for Advanced and Locally advanced oesophagogastric cancer-2; n = 1002) and ML17032 (n = 316). REAL-2 randomised patients to four regimens (ECF, ECX, EOF and EOX) to compare 5-FU with capecitabine and cisplatin with oxaliplatin, whereas ML17032 compared CX with CF. Efficacy outcomes from these trials were pooled in an individual patient data (IPD) meta-analysis. Both RCTs demonstrated statistically significant non-inferiority of capecitabine on the outcome of overall survival (OS) assessed in the per-protocol population; equivalent results were also demonstrated for progression-free survival (PFS). The IPD meta-analysis found a statistically significant benefit in OS for capecitabine compared with 5-FU [unadjusted hazard ratio (HR): 0.87; 95% confidence interval (CI) 0.77 to 0.98, p = 0.027]. There was no evidence of a poorer safety profile for capecitabine overall, nor of any difference in quality of life (QoL) between the two fluoropyrimidines. The MS included a de novo economic evaluation based on a cost-minimisation analysis (CMA), where the costs of capecitabine-based regimens were compared with their equivalent 5-FU-based regimens in aGC. A time horizon of 5.5 cycles (each lasting for 21 days) was used in the base-case analysis, representing the duration of treatment. The results of the manufacturer’s base-case analysis showed that capecitabine regimens are associated with mean net cost savings of £1620 (ECX vs ECF), £1572 (EOX vs EOF) and £4210 (CX vs CF). The manufacturer failed to comment explicitly on the uncertainty around the estimates of efficacy and on the fact that the IPD meta-analysis suggests that capecitabine may actually be more effective on average. Further analyses exploring additional costs incurred by the UK NHS from extending survival duration showed that these are unlikely to have a material effect on conclusions. A full probabilistic analysis was not performed; however, the evidence explored by the MS and ERG is consistent in suggesting that capecitabine has a lower mean cost than 5-FU-based regimens. The submission was considered to contain convincing evidence of the non-inferiority of capecitabine to 5-FU on survival; this evidence was considered to be applicable to UK practice. Although some uncertainty remains, the ERG deemed CMA to be an appropriate framework with which to analyse this decision problem. Overall cost estimates for the CMA were generated appropriately and were robust to uncertainties regarding assumptions and sources. At the time of writing, the guidance document issued by NICE on 28 July 2010 states that capecitabine in combination with a platinum-based regimen is recommended for the first-line treatment of inoperable advanced gastric cancer.

Absence of P-selectin in recipients of allogeneic bone marrow transplantation ameliorates experimental graft-versus-host disease

Alloreactive T cells are crucial for graft-versus-host disease (GVHD) pathophysiology, and modulating their trafficking patterns has been efficacious in ameliorating experimental disease. We report in this paper that P-selectin, a glycoprotein found on resting and inflamed endothelium, is important for donor alloreactive T cells trafficking into GVHD target organs, such as the intestines and skin. Compared with wild-type (WT) recipients of allogeneic bone marrow transplantation, P-selectin(-/-) recipients exhibit decreased GVHD mortality and decreased GVHD of the skin, liver, and small bowels. This was associated with diminished infiltration of alloactivated T cells into the Peyer's patches and small bowels, coupled with increased numbers of donor T cells in the spleen and secondary lymphoid organs (SLOs). Surprisingly, however, donor T cells deficient for P-selectin glycoprotein ligand 1, the most well described P-selectin ligand, mediated GVHD similar to WT T cells and accumulated in SLO and target organs in similar numbers as WT T cells. This suggests that P-selectin may be required for trafficking into inflamed tissues but not SLO and that donor T cells may use multiple P-selectin ligands apart from P-selectin glycoprotein ligand 1 to interact with P-selectin and traffic into inflamed tissues during GVHD. We conclude that targeting P-selectin may be a viable strategy for GVHD prophylaxis or treatment.

Inhibition of neovascularization to simultaneously ameliorate graft-vs-host disease and decrease tumor growth

BACKGROUND Blood vessels are formed either by sprouting of resident tissue endothelial cells (angiogenesis) or by recruitment of bone marrow (BM)-derived circulating endothelial progenitor cells (EPCs, vasculogenesis). Neovascularization has been implicated in tumor growth and inflammation, but its roles in graft-vs-host disease (GVHD) and in tumors after allogeneic BM transplantation (allo-BMT) were not known. METHODS We analyzed neovascularization, the contribution of endothelial cells and EPCs, and the ability of anti-vascular endothelial-cadherin antibody, E4G10, to inhibit neovascularization in mice with GVHD after allo-BMT using immunofluorescence microscopy and flow cytometry. We examined survival and clinical and histopathologic GVHD in mice (n = 10-25 per group) in which GVHD was treated with the E4G10 antibody using immunohistochemistry, flow cytometry, and cytokine immunoassay. We also assessed survival, the contribution of green fluorescent protein-marked EPCs to the tumor vasculature, and the ability of E4G10 to inhibit tumor growth in tumor-bearing mice (n = 20-33 per group) after allo-BMT using histopathology and bioluminescence imaging. All statistical tests were two-sided. RESULTS We found increased neovascularization mediated by vasculogenesis, as opposed to angiogenesis, in GVHD target tissues, such as liver and intestines. Administration of E4G10 inhibited neovascularization by donor BM-derived cells without affecting host vascularization, inhibited both GVHD and tumor growth, and increased survival (at 60 days post-BMT and tumor challenge with A20 lymphoma, the probability of survival was 0.29 for control antibody-treated allo-BMT recipients vs 0.7 for E4G10-treated allo-BMT recipients, 95% confidence interval = 0.180 to 0.640, P < .001). CONCLUSIONS Therapeutic targeting of neovascularization in allo-BMT recipients is a novel strategy to simultaneously ameliorate GVHD and inhibit posttransplant tumor growth, providing a new approach to improve the overall outcome of allogeneic hematopoietic stem cell transplantation.

The cytolytic molecules Fas ligand and TRAIL are required for murine thymic graft-versus-host disease

Thymic graft-versus-host disease (tGVHD) can contribute to profound T cell deficiency and repertoire restriction after allogeneic BM transplantation (allo-BMT). However, the cellular mechanisms of tGVHD and interactions between donor alloreactive T cells and thymic tissues remain poorly defined. Using clinically relevant murine allo-BMT models, we show here that even minimal numbers of donor alloreactive T cells, which caused mild nonlethal systemic graft-versus-host disease, were sufficient to damage the thymus, delay T lineage reconstitution, and compromise donor peripheral T cell function. Furthermore, to mediate tGVHD, donor alloreactive T cells required trafficking molecules, including CCR9, L selectin, P selectin glycoprotein ligand-1, the integrin subunits alphaE and beta7, CCR2, and CXCR3, and costimulatory/inhibitory molecules, including Ox40 and carcinoembryonic antigen-associated cell adhesion molecule 1. We found that radiation in BMT conditioning regimens upregulated expression of the death receptors Fas and death receptor 5 (DR5) on thymic stromal cells (especially epithelium), while decreasing expression of the antiapoptotic regulator cellular caspase-8-like inhibitory protein. Donor alloreactive T cells used the cognate proteins FasL and TNF-related apoptosis-inducing ligand (TRAIL) (but not TNF or perforin) to mediate tGVHD, thereby damaging thymic stromal cells, cytoarchitecture, and function. Strategies that interfere with Fas/FasL and TRAIL/DR5 interactions may therefore represent a means to attenuate tGVHD and improve T cell reconstitution in allo-BMT recipients.