Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

FDG-PET/CT after two cycles of R-CHOP in DLBCL predicts complete remission but has limited value in identifying patients with poor outcome - final result of a UK National Cancer Research Institute prospective study

The UK National Cancer Research Institute initiated a prospective study (UKCRN-ID 1760) to assess the prognostic value of early fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) in diffuse large B-cell lymphoma (DLBCL). In total, 189 patients with DLBCL treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) had baseline and post-cycle-2 PET (PET2) within a quality assurance framework. Treatment decisions were based on CT; PET2 was archived for central blinded reporting after treatment completion. The association of PET2 response with end-of-treatment CT, progression-free (PFS) and overall survival (OS) was explored. The end-of-treatment complete response rate on CT was 83·9%, 75·0%, 70·5%, 40·4% and 36·4% for Deauville score (DS) 1 (n = 34), 2 (n = 39), 3 (n = 46), 4 (n = 56) and 5 (n = 14) (P < 0·001); and 64·1% and 50·0% for the maximum standardised uptake value (∆SUV_max ) of ≥66% (n = 168) and <66% (n = 21), respectively (P = 0·25). After a median 5·4 years of follow-up, the 5-year PFS was 69·4%, 72·8%, 76·7%, 71·2% and 47·6% by DS 1-5 (P = 0·01); and 72·6% and 57·1% by ∆SUV_max of ≥66% and <66% (P = 0·03), respectively. The association with DS remained in multivariable analyses, and was consistent for OS. Early complete metabolic response (DS 1-3) at interim PET/CT after two cycles of R-CHOP in DLBCL was associated with a higher end-of-treatment complete and overall response rate; however, only DS-5 patients had inferior PFS and OS.

Favourable outcomes for high-risk diffuse large B-cell lymphoma (IPI 3-5) treated with front-line R-CODOX-M/R-IVAC chemotherapy: results of a phase 2 UK NCRI trial

Background

Outcomes for patients with high-risk diffuse large B-cell lymphoma (DLBCL) treated with R-CHOP chemotherapy are suboptimal but, to date, no alternative regimen has been shown to improve survival rates. This phase 2 trial aimed to assess the efficacy of a Burkitt-like approach for high-risk DLBCL using the dose-intense R-CODOX-M/R-IVAC regimen.

Patients and methods

Eligible patients were aged 18–65 years with stage II–IV untreated DLBCL and an International Prognostic Index (IPI) score of 3–5. Patients received alternating cycles of CODOX-M (cyclophosphamide, vincristine, doxorubicin and high-dose methotrexate) alternating with IVAC chemotherapy (ifosfamide, etoposide and high-dose cytarabine) plus eight doses of rituximab. Response was assessed by computed tomography after completing all four cycles of chemotherapy. The primary end point was 2-year progression-free survival (PFS).

Results

A total of 111 eligible patients were registered; median age was 50 years, IPI score was 3 (60.4%) or 4/5 (39.6%), 54% had a performance status ≥2 and 9% had central nervous system involvement. A total of 85 patients (76.6%) completed all four cycles of chemotherapy. There were five treatment-related deaths (4.3%), all in patients with performance status of 3 and aged >50 years. Two-year PFS for the whole cohort was 67.9% [90% confidence interval (CI) 59.9–74.6] and 2-year overall survival was 76.0% (90% CI 68.5–82.0). The ability to tolerate and complete treatment was lower in patients with performance status ≥2 who were aged >50 years, where 2-year PFS was 43.5% (90% CI 27.9–58.0).

Conclusions

This trial demonstrates that R-CODOX-M/R-IVAC is a feasible and effective regimen for the treatment of younger and/or fit patients with high-risk DLBCL. These encouraging survival rates demonstrate that this regimen warrants further investigation against standard of care.

Trial Registration

ClinicalTrials.gov (NCT00974792) and EudraCT (2005-003479-19).

•

R-CODOX-M/R-IVAC is an effective regimen for treatment of high-risk DLBCL and high-grade B-cell lymphoma (IPI score 3–5).

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Treatment was well tolerated in patients aged <50 years, or aged 50–65 with performance status 0 or 1.

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The 2-year PFS was 67.9% (90% CI: 59.9–74.6) for the whole cohort.

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This regimen warrants further evaluation against standard of care in high-risk DLBCL.

Prognostic indices in diffuse large B-cell lymphoma in the rituximab era: an analysis of the UK National Cancer Research Institute R-CHOP 14 versus 21 phase 3 trial

We compared the International Prognostic Index (IPI), Revised (R)-IPI and age-adjusted (aa)-IPI as prognostic indices for patients with diffuse large B-cell lymphoma (DLBCL) in the UK National Cancer Research Institute (NCRI) R-CHOP 14 versus 21 trial (N = 1080). The R-IPI and aa-IPI showed no marked improvement compared to the IPI for overall and progression-free survival, in terms of model fit or discrimination. Similar results were observed in exploratory analyses incorporating the Grupo Español de Linfomas/Transplante de Médula Ósea (GELTAMO)-IPI, where baseline β2-microglobulin data were available (N = 655). Although our findings support current use of the IPI, a novel prognostic tool to better delineate a high-risk DLBCL group in the rituximab era is needed.

Favourable outcomes for high‐risk Burkitt lymphoma patients (IPI 3‐5) treated with rituximab plus CODOX‐M/IVAC: Results of a phase 2 UK NCRI trial

Introduction

Outcomes after frontline treatment of Burkitt lymphoma (BL) have improved with the introduction of dose‐intense chemotherapy regimens, such as CODOX‐M/IVAC. While rituximab has increased survival rates for most forms of high‐grade B‐cell lymphoma, there has previously been hesitancy about incorporating it into BL treatment, partly due to concerns about increased toxicity. Prospective data using the standard dose CODOX‐M/IVAC regimen in combination with rituximab are lacking. We conducted a single‐arm phase 2 trial to assess the efficacy and toxicity of R‐CODOX‐M/R‐IVAC.

Methods

Eligible patients were aged 18–65 years, with newly diagnosed BL with MYC rearrangement as the sole cytogenetic abnormality, and high‐risk disease, defined by an International Prognostic Index (IPI) score of 3‐5. Patients received two cycles of R‐CODOX‐M chemotherapy alternating with two cycles of R‐IVAC, followed by two further cycles of rituximab alone. The primary endpoint was 2‐year progression‐free survival.

Results

Thirty‐eight patients were registered but after central pathology review, 27 patients had confirmed BL and commenced study treatment. Median age was 35 years, 14.8% patients had central nervous system involvement and 18.5% were HIV positive. Twenty‐two (81.4%) patients completed four cycles of chemotherapy. There were two treatment‐related deaths (7.4%). Two‐year progression‐free and overall survival rates were 77.2% (90% confidence interval [CI]: 56.0‐89.0) and 80.7% (90% CI: 59.6‐91.5), respectively.

Conclusions

This prospective trial demonstrates excellent survival rates with R‐CODOX‐M/R‐IVAC in a high‐risk BL cohort. It provides reassuring evidence regarding the feasibility of this regimen and also provides a benchmark for future studies.

A toolbox for the longitudinal assessment of healthspan in aging mice

The number of people aged over 65 is expected to double in the next 30 years. For many, living longer will mean spending more years with the burdens of chronic diseases such as Alzheimer's disease, cardiovascular disease, and diabetes. Although researchers have made rapid progress in developing geroprotective interventions that target mechanisms of aging and delay or prevent the onset of multiple concurrent age-related diseases, a lack of standardized techniques to assess healthspan in preclinical murine studies has resulted in reduced reproducibility and slow progress. To overcome this, major centers in Europe and the United States skilled in healthspan analysis came together to agree on a toolbox of techniques that can be used to consistently assess the healthspan of mice. Here, we describe the agreed toolbox, which contains protocols for echocardiography, novel object recognition, grip strength, rotarod, glucose tolerance test (GTT) and insulin tolerance test (ITT), body composition, and energy expenditure. The protocols can be performed longitudinally in the same mouse over a period of 4-6 weeks to test how candidate geroprotectors affect cardiac, cognitive, neuromuscular, and metabolic health.

6089Increased vascular endothelial growth factor signalling following loss of endothelial endoglin leads to peripheral arteriovenous shunting and high output heart failure

Background

Endoglin is a co-receptor for TGFbeta/BMP9/10 signalling and ENG mutations lead to the vascular disorder hereditary haemorrhagic telangiectasia type I (HHT). Endoglin is also required for normal vascular development and angiogenesis, but little is known about endoglin's role in quiescent adult vascular endothelium.

Purpose

The goal of this present study is to determine how endoglin maintains vessel calibre in adult life to prevent AVM formation and thereby protect heart function.

Methods

To investigate this role, tamoxifen was administered to adult Cdh5(PAC)-CreERT2; Engfl/fl mice to generate endothelial-specific depletion of endoglin (Eng-iKOe). Cardiac magnetic resonance imaging, myography, vascular casting, microsphere injection, immunohistology, qPCR and aortic telemetry were used to evaluate cardiovascular changes after endoglin knockdown.

Results

Endothelial-specific loss of endoglin leads to an enlarged heart and cardiomyocyte hypertrophy within 5 weeks, progressing to high output heart failure (HOHF). In vivo aortic telemetry revealed significant loss of aortic pressure within a few days of endoglin depletion. Increased cardiac size and reduced cardiac afterload were confirmed by ventricular pressure loop analysis. As HOHF could result from arteriovenous malformations (AVMs), and these are found primarily in mucocutaneous and pulmonary tissues in HHT, we systematically screened for AVMs using microspheres and vascular casting. Although AVMs were absent in the majority of tissues, they were observed in the pelvic region and may account for the rapid increase in cardiac output. The pelvic cartilaginous symphysis is a noncapsulated cartilage with a naturally high endogenous expression of vascular endothelial growth factor (VEGF). Development of pelvic AVMs in this region of high VEGF expression occurred because loss of endoglin in endothelial cells leads to increased sensitivity to VEGF and a hyper-proliferative response. Finally, we found that inhibition of VEGFR2 was protective against AVMs development, enlargement of the heart and dilatation of the ventricles.

Conclusion

Our results showed the essential role of endoglin in the maintenance of adult cardio-vasculature through crosstalk with the VEGF signalling pathway.

Acknowledgement/Funding

British Heart Foundation, Cure HHT, The Swedish Research Council, The Cardiovascular Programme at Karolinska Institutet, The Swedish Cancer Society

Central nervous system relapse of diffuse large B-cell lymphoma in the rituximab era: results of the UK NCRI R-CHOP-14 versus 21 trial

Background

Central nervous system (CNS) relapse of diffuse large B-cell lymphoma (DLBCL) is associated with a dismal prognosis. Here, we report an analysis of CNS relapse for patients treated within the UK NCRI phase III R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone) 14 versus 21 randomised trial.

Patients and methods

The R-CHOP 14 versus 21 trial compared R-CHOP administered two- versus three weekly in previously untreated patients aged ≥18 years with bulky stage I–IV DLBCL (n = 1080). Details of CNS prophylaxis were retrospectively collected from participating sites. The incidence and risk factors for CNS relapse including application of the CNS-IPI were evaluated.

Results

177/984 patients (18.0%) received prophylaxis (intrathecal (IT) methotrexate (MTX) n = 163, intravenous (IV) MTX n = 2, prophylaxis type unknown n = 11 and IT MTX and cytarabine n = 1). At a median follow-up of 6.5 years, 21 cases of CNS relapse (isolated n = 11, with systemic relapse n = 10) were observed, with a cumulative incidence of 1.9%. For patients selected to receive prophylaxis, the incidence was 2.8%. Relapses predominantly involved the brain parenchyma (81.0%) and isolated leptomeningeal involvement was rare (14.3%). Univariable analysis demonstrated the following risk factors for CNS relapse: performance status 2, elevated lactate dehydrogenase, IPI, >1 extranodal site of disease and presence of a ‘high-risk’ extranodal site. Due to the low number of events no factor remained significant in multivariate analysis. Application of the CNS-IPI revealed a high-risk group (4-6 risk factors) with a 2- and 5-year incidence of CNS relapse of 5.2% and 6.8%, respectively.

Conclusion

Despite very limited use of IV MTX as prophylaxis, the incidence of CNS relapse following R-CHOP was very low (1.9%) confirming the reduced incidence in the rituximab era. The CNS-IPI identified patients at highest risk for CNS recurrence.

ClinicalTrials.gov

ISCRTN number 16017947 (R-CHOP14v21); EudraCT number 2004-002197-34.

Outcome of elderly patients with diffuse large B-cell lymphoma treated with R-CHOP: results from the UK NCRI R-CHOP14v21 trial with combined analysis of molecular characteristics with the DSHNHL RICOVER-60 trial

BACKGROUND

There is an on-going debate whether 2- or 3-weekly administration of R-CHOP is the preferred first-line treatment for elderly patients with diffuse large B-cell lymphoma (DLBCL). The UK NCRI R-CHOP14v21 randomized phase 3 trial did not demonstrate a difference in outcomes between R-CHOP-14 and R-CHOP-21 in newly diagnosed DLBCL patients aged 19-88 years, but data on elderly patients have not been reported in detail so far. Here, we provide a subgroup analysis of patients ≥60 years treated on the R-CHOP14v21 trial with extended follow-up.

PATIENTS AND METHODS

Six hundred and four R-CHOP14v21 patients ≥60 years were included in this subgroup analysis, with a median follow-up of 77.7 months. To assess the impact of MYC rearrangements (MYC-R) and double-hit-lymphoma (DHL) on outcome in elderly patients, we performed a joint analysis of cases with available molecular data from the R-CHOP14v21 (N = 217) and RICOVER-60 (N = 204) trials.

RESULTS

Elderly DLBCL patients received high dose intensities with median total doses of ≥98% for all agents. Toxicities were similar in both arms with the exception of more grade ≥3 neutropenia (P < 0.0001) and fewer grade ≥3 thrombocytopenia (P = 0.05) in R-CHOP-21 versus R-CHOP-14. The elderly patient population had a favorable 5-year overall survival (OS) of 69% (95% CI: 65-73). We did not identify any subgroup of patients that showed differential response to either regimen. In multivariable analysis including individual factors of the IPI, gender, bulk, B2M and albumin levels, only age and B2M were of independent prognostic significance for OS. Molecular analyses demonstrated a significant impact of MYC-R (HR = 1.96; 95% CI: 1.22-3.16; P = 0.01) and DHL (HR = 2.21; 95% CI: 1.18-4.11; P = 0.01) on OS in the combined trial cohorts, independent of other prognostic factors.

CONCLUSIONS

Our data support equivalence of both R-CHOP application forms in elderly DLBCL patients. Elderly MYC-R and DHL patients have inferior prognosis and should be considered for alternative treatment approaches.

TRIAL NUMBERS

ISCRTN 16017947 (R-CHOP14v21); NCT00052936 (RICOVER-60).

Hypoxia determines survival outcomes of bacterial infection through HIF-1alpha dependent re-programming of leukocyte metabolism

Hypoxia and bacterial infection frequently co-exist, in both acute and chronic clinical settings, and typically result in adverse clinical outcomes. To ameliorate this morbidity, we investigated the interaction between hypoxia and the host response. In the context of acute hypoxia, both S. aureus and S. pneumoniae infections rapidly induced progressive neutrophil mediated morbidity and mortality, with associated hypothermia and cardiovascular compromise. Preconditioning animals through longer exposures to hypoxia, prior to infection, prevented these pathophysiological responses and profoundly dampened the transcriptome of circulating leukocytes. Specifically, perturbation of HIF pathway and glycolysis genes by hypoxic preconditioning was associated with reduced leukocyte glucose utilisation, resulting in systemic rescue from a global negative energy state and myocardial protection. Thus we demonstrate that hypoxia preconditions the innate immune response and determines survival outcomes following bacterial infection through suppression of HIF-1α and neutrophil metabolism. The therapeutic implications of this work are that in the context of systemic or tissue hypoxia therapies that target the host response could improve infection associated morbidity and mortality.

Rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone (R-CHOP) in the management of primary mediastinal B-cell lymphoma: a subgroup analysis of the UK NCRI R-CHOP 14 versus 21 trial

We performed a subgroup analysis of the phase III UK National Cancer Research Institute R-CHOP-14 versus R-CHOP-21 (two- versus three-weekly rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone) trial to evaluate the outcomes for 50 patients with World Health Organization 2008 classified primary mediastinal B-cell lymphoma identified from the trial database. At a median follow-up of 7·2 years the 5-year progression-free survival and overall survival was 79·8% and 83·8%, respectively. An exploratory analysis raised the possibility of a better outcome in those who received R-CHOP-14 and time intensification may still, in the rituximab era, merit testing in a randomised trial in this subgroup of patients.

Osteoprotegerin in Cardiometabolic Disorders

Osteoprotegerin (OPG), a glycoprotein traditionally implicated in bone remodelling, has been recently related to cardiovascular disease (CVD). Human studies show a positive relationship between circulating OPG, vascular damage, and CVD, and as such OPG has emerged as a potential biomarker for CVD. This review focuses on the relationship between circulating OPG and different endocrine cardiometabolic alterations such as type 1 and 2 diabetes. The association of OPG with diabetic complications (neuropathy, nephropathy, or retinopathy) as well as with atherosclerosis, coronary artery calcification, morbidity, and mortality is pointed out. Moreover, OPG modulation by different treatments is also established. Besides, other associated diseases such as obesity, hypertension, and metabolic syndrome, which are known cardiovascular risk factors, are also considered.

A report on the use of animal models and phenotyping methods in pulmonary hypertension research

The failure to translate positive results from preclinical studies into new clinical therapies is a major problem throughout medical research. Specifically, in pulmonary hypertension, numerous research studies have shown beneficial effects of new therapies in experimental models, but these have largely failed to translate into clinical benefit in human trials. This is undoubtedly due, at least in part, to inadequacies of the models, but while monogenic animal models will never fully recapitulate human disease, they do still provide the best platform on which to test novel therapeutic agents. In the postgenomic era, there is emphasis on a greater understanding of disease pathogenesis, which has subsequently led to the development of both new targets and new models in which to test them. The evolution of new technologies means that we are now better equipped to phenotype these models, but the level of detail provided varies dramatically throughout the literature. However, subtle variances in experimental methods can make comparing data/findings between research laboratories difficult and are a possible contributing factor to variance between preclinical and clinical data. The aim of this report was to capture information on current practice for use of the growing array of animal models, to help movement toward developing guidelines and standards for the "best" use of animal models of pulmonary hypertension.

Influence of pre-analytical and analytical factors on osteoprotegerin measurements

INTRODUCTION

Osteoprotegerin (OPG), an osteoclastogenesis inhibitor implicated in bone remodelling, has emerged as a potential biomarker for cardiovascular disease. In order to implement OPG determination in the clinical laboratory, it is crucial to identify the most appropriate specimen type, preparation and measurement conditions. The present study focuses on identifying the pre-analytical variables that may influence OPG measurements.

METHODS

Serum and plasma (in EDTA, heparin and citrate) were collected from 45 healthy volunteers (men (n=21, 46.7%), women (n=24, 53.3%)). OPG was analysed by ELISA. The influence of the centrifugation speed, the number of freeze-thaw cycles, delay in sample processing, thermo-stability and endogenous interfering agents (haemolysis, triglycerides, bilirubin, cholesterol and RANKL) were studied.

RESULTS

OPG concentrations were significantly lower (p<0.0001) in serum (1015±357 pg/mL) than in all plasma samples (1314±448 pg/mL in EDTA, 1209±417 pg/mL in heparin and 1260±498 pg/mL in citrate). Increasing centrifugation speed (200 g to 3000 g) did not change serum OPG concentration (p=0.88). However, OPG concentration significantly increased when centrifuged serum samples were stored at 48 h at room temperature (p<0.0001). Repeated freeze-thaw cycles did not modify OPG levels until 4 cycles (p<0.0001). Increasing time before processing the samples (2 h and 6 h) raised OPG concentrations both at room temperature (p<0.0001) or 4°C (p<0.001). Positive concentration-dependent interference of triglycerides was found in the analysed pooled samples; however, OPG concentrations were falsely diminished with haemoglobin interference. Bilirubin, cholesterol and RANKL did not interfere with OPG measurements.

Risk factors and medical follow-up of drug users tested for hepatitis C--can the risk of transmission be reduced?

Of 1728 patients attending a regional drug and alcohol clinic, 202 were considered at risk of hepatitis C virus (HCV). Forty-nine per cent (99/202) agreed to testing-67% (67) were HCV antibody positive. Age and a history of needle sharing was the significant factor associated with positive HCV status. Patients on methadone maintenance medication were more-likely to have been HCV positive, but significantly (p = 0.005) less likely to have shared needles in the previous year. Seventy-three per cent (49/67) attended for follow-up at a "liver clinic". Fifty per cent were infected with genotype 1a. Eighteen patients were biopsied and all were abnormal, ranging from mild hepatitis to severe fibrotic hepatitis. Attendance for medical follow-up was poor, which emphasizes the importance of preventative measures such as methadone maintenance programmes for reducing the spread of HCV.

Control of eosinophil toxicity in the lung

The inappropriate accumulation of eosinophils and the subsequent release of their potent pro-inflammatory mediator arsenal are thought to be important contributors to the pathogenesis of asthma and other allergic diseases. It is also becoming apparent that eosinophils may play a role in the orchestration of immune responses in the asthmatic lung. There is therefore much interest in the development of strategies to limit or prevent eosinophil-induced toxicity. The mechanisms by which eosinophils accumulate in the peribronchial tissues of the lung are complex and include enhanced differentiation and release from the bone marrow, selective adhesion and transendothelial migration, directed movement in response to specific chemotactic mediators and finally prolonged survival as a consequence of delayed apoptosis. Thus it can be appreciated that there are many points at which the toxicity of eosinophils can be limited or even prevented. Important areas for potential advances in glucocorticoid (GC) development include efforts to dissociate their anti-inflammatory effects from unwanted side effects. Other areas include the development of humanized monoclonal antibodies against IL-4, IL-13 and IL-5 together with the inhibition of adhesion pathways and/or chemokines responsible for eosinophil accumulation in the asthmatic lung. Several avenues of research are currently underway in an attempt to define mechanisms by which pro-inflammatory cells such as eosinophils can be safely removed from the asthmatic lung through apoptosis induction and their subsequent ingestion by phagocytes. This review will discuss both the potential and shortcomings of these diverse approaches to limit eosinophil toxicity in the asthmatic lung.

Ultrasound-mediated delivery of TIMP-3 plasmid DNA into saphenous vein leads to increased lumen size in a porcine interposition graft model

Progressive saphenous vein graft (SVG) narrowing and occlusion remains a major limitation of coronary artery bypass grafting and is an important target for gene therapy. Ex vivo adenoviral gene transfer of tissue inhibitor of metalloproteinase 3 (TIMP-3) reduces adverse SVG remodelling postarterialization, but concerns remain over the use of viral vectors in patients. Ultrasound exposure (USE) in the presence of echocontrast microbubbles (ECM) substantially enhances nonviral gene delivery. We investigated the effects of ultrasound-enhanced gene delivery (UEGD) of TIMP-3 plasmid on vascular remodelling in porcine SVG. Maximal luciferase activity (3000-fold versus naked plasmid alone) and TIMP-3 transgene expression in porcine vascular smooth muscle cells in vitro was achieved using USE at 1 MHz, 1.8 mechanical index (MI), 6% duty cycle (DC) in the presence of 50% (v/v) BR14 ECM (Bracco). These conditions were therefore utilized for subsequent studies in vivo. Yorkshire White pigs received carotid interposition SVG that were untransfected or had undergone ex vivo UEGD of lacZ (control) or TIMP-3 plasmids. At 28 d postgrafting, lumen and total vessel area were significantly greater in the TIMP-3 group (10.1+/-1.2 and 25.5+/-2.2 mm2, respectively) compared to untransfected (6.34+/-0.5 and 20.8+/-1.9 mm2) or lacZ-transfected (6.1+/-0.7 and 19.7+/-1.2 mm2) controls (P<0.01). These data indicate that nonviral TIMP-3 plasmid delivery by USE achieves significant biological effects in a clinically relevant model of SV grafting, and is the first study to demonstrate the potential for therapeutic UEGD to prevent SVG failure.

Reduced eosinophil apoptosis in induced sputum correlates with asthma severity

This study was carried out to investigate the relationship between induced sputum eosinophil apoptosis and clinical severity score, airway obstruction and symptom scores in patients with chronic stable asthma. Altogether, 41 chronic stable asthmatic subjects of varying severity defined by Aas score and 17 control subjects underwent spirometry, symptom questionnaire and successful sputum induction. Sputum was processed and cytospins prepared for light microscopy to determine normal and apoptotic eosinophils. Mild asthmatic subjects had a significantly lower percentage sputum eosinophils and a significantly higher eosinophil apoptotic ratio (AR) than moderate or chronic severe asthmatics. Severe asthmatic subjects had a significantly greater age, duration of asthma and sputum eosinophil count x mL(-1) than mild asthmatic subjects. Asthmatic subjects' symptom scores, severity scores and age inversely correlated with AR and the percentage of sputum eosinophils. Baseline forced expiratory volume in one second inversely correlated with percentage sputum eosinophils and positively correlated with AR. The study demonstrates a relationship between reduced sputum eosinophil apoptosis and increased clinical severity of chronic stable asthma, providing additional evidence that eosinophil apoptosis may be important in the resolution of eosinophilic airway inflammation in asthma.

Eosinophils from patients with asthma express higher levels of the pan-leucocyte receptor CD45 and the isoform CD45RO

BACKGROUND

Eosinophils and their secreted mediators are heavily implicated as effector cells in asthma and other allergic diseases. Comparisons were made between expression of CD45, CD45RA, CD45RB and CD45RO by eosinophils from asthmatic patients and non-asthmatic atopic and non-atopic, non-asthmatic control subjects.

METHODS

Twenty-seven patients with asthma and 33 control subjects were recruited for the study. Eosinophil expression of CD45, CD45RA, CD45RB and CD45RO was established by immunostaining and flow cytometry was performed on whole leucocyte samples. Eosinophil apoptosis in response to CD45 and CD45 isoform monoclonal antibody (mAb)-dependent receptor ligation was assessed by binding of annexin V and flow cytometry.

RESULTS

Eosinophils from patients with asthma expressed significantly (P<0.05) higher levels of pan-CD45 and CD45RO compared with eosinophils from non-asthmatic, non-atopic subjects. No significant correlations were found between expression of either pan-CD45 or CD45RO and the degree of symptoms in the asthmatic patients as defined by lung function (FEV1 and FEF25-75) and methacholine PD20. Increased expression of pan-CD45 or CD45RO did not appear to be a consequence of the atopic phenotype. Higher expression of pan-CD45 or CD45RO by eosinophils from asthmatic patients was not associated with greater sensitivity to CD45 and CD45RO mAb receptor ligation-induced eosinophil apoptosis.

CONCLUSION

Higher expression of CD45 and CD45RO by eosinophils from asthmatic patients appeared to be a consequence of asthma rather than atopy and further supports a role for activated eosinophils in asthma.

Ultrasound gene therapy: on the road from concept to reality

The promise of gene therapy lies in the potential to ameliorate or cure conditions that are resistant to conventional therapeutic approaches. Progress in vascular and all other fields of gene therapy has been hampered by concerns over the safety and practicality of recombinant viral vectors and the inefficiency of current nonviral transfection techniques. This review summarizes the increasing evidence that exposure of eukaryotic cells to relatively modest intensity ultrasound, within the range emitted by diagnostic transducers, either alone or in combination with other nonviral techniques, can enhance transgene expression by up to several orders of magnitude over naked DNA alone. In combination with the flexibility and excellent clinical safety profile of therapeutic and diagnostic ultrasound, these data suggest that ultrasound-assisted gene delivery has great promise as a novel approach to improve the efficiency of many forms of nonviral gene delivery.

Microbubble-enhanced ultrasound for vascular gene delivery

Progress in cardiovascular gene therapy has been hampered by concerns over the safety and practicality of viral vectors and the inefficiency of current nonviral transfection techniques. We have previously reported that ultrasound exposure (USE) enhances transgene expression in vascular cells by up to 10-fold after naked DNA transfection, and enhances lipofection by up to three-fold. We report here that performing USE in the presence of microbubble echocontrast agents enhances acoustic cavitation and is associated with approximately 300-fold increments in transgene expression after naked DNA transfections. This approach also enhances by four-fold the efficiency of polyplex transfection, yielding transgene expression levels approximately 3000-fold higher than after naked DNA alone. These data indicate an important role for acoustic cavitation in the effects of USE. Ultrasound can be focused upon almost any organ and hence this approach holds promise as a means to deliver targeted gene therapy in cardiovascular conditions such as such angioplasty restenosis and in many other clinical situations.

Ultrasound enhances reporter gene expression after transfection of vascular cells in vitro

BACKGROUND

Restenosis after percutaneous coronary intervention remains a serious clinical problem. Progress in local gene therapy to prevent restenosis has been hindered by concerns over the safety and efficacy of viral vectors and the limited efficiency of nonviral techniques. This study investigates the use of adjunctive ultrasound to enhance nonviral gene delivery.

METHODS AND RESULTS

Cultured porcine vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) were transfected with naked or liposome-complexed luciferase reporter plasmid for 3 hours. Ultrasound exposure (USE) for 60 seconds at 1 MHz, 0.4 W/cm2, 30 minutes into this transfection period enhanced luciferase activity 48 hours later by 7.5-fold and 2. 4-fold, respectively. Luciferase activity after lipofection of ECs was similarly enhanced 3.3-fold by adjunctive USE. USE had no effect on cell viability, although it inhibited VSMC but not EC proliferation.

CONCLUSIONS

Adjunctive USE was associated with enhanced transgene expression in VSMCs and ECs and reduced VSMC but not EC proliferation in vitro, which suggests that ultrasound-assisted local gene therapy has potential as an antirestenotic therapy.

Indirubin, the active constituent of a Chinese antileukaemia medicine, inhibits cyclin-dependent kinases

Indirubin is the active ingredient of Danggui Longhui Wan, a mixture of plants that is used in traditional Chinese medicine to treat chronic diseases. Here we identify indirubin and its analogues as potent inhibitors of cyclin-dependent kinases (CDKs). The crystal structure of CDK2 in complex with indirubin derivatives shows that indirubin interacts with the kinase's ATP-binding site through van der Waals interactions and three hydrogen bonds. Indirubin-3'-monoxime inhibits the proliferation of a large range of cells, mainly through arresting the cells in the G2/M phase of the cell cycle. These results have implications for therapeutic optimization of indigoids.

A randomised comparison of oral and vaginal misoprostol for cervical priming before suction termination of pregnancy

OBJECTIVE

To assess the effectiveness and acceptability of oral misoprostol, self-administered 12 h before surgery, as a cervical priming agent prior to day case suction termination of pregnancy.

DESIGN

Randomised trial comparing oral misoprostol with the local standard regimen of vaginal misoprostol.

SUBJECTS

Sixty consecutive women scheduled for day case suction termination in one gynaecology unit.

INTERVENTIONS

Cervical priming with misoprostol 400 mg orally, 12 h prior to surgery or 800 mg vaginally, two to four hours prior to surgery.

MAIN OUTCOME MEASURES

Basal cervical dilatation, cumulative force required to dilate the cervix to 9 mm, operative blood loss and side effects (nausea, vomiting, diarrhoea, abdominal pain and vaginal bleeding).

RESULTS

There were no significant differences between the oral and vaginal treatment groups in relation to basal dilatation, cumulative force to achieve 9 mm dilatation or gastrointestinal side effects. However, those in the oral group experienced more severe pain and heavier pre-operative bleeding. Two patients in the oral group experienced incomplete abortion at home after taking misoprostol and a further patient required early admission because of heavy bleeding.

CONCLUSIONS

Because of the unpredictability of action of oral misoprostol, with incomplete abortion or heavy bleeding occurring prior to admission in three patients, we cannot recommend the dosage schedule evaluated here for routine clinical use.