A randomised trial of a T2-composite-biomarker strategy adjusting corticosteroidtreatment in severe asthma, a post- hoc analysis by sex

BACKGROUND

Approximately 5-10% of patients with asthma have severe disease with a consistent preponderance in females. Current asthma guidelines recommend stepwise treatment to achieve symptom control with no differential treatment considerations for either sex.

OBJECTIVES

To examine whether patient sex affects outcomes when using a composite T2-biomarker score to adjust corticosteroid treatment in patients with severe asthma compared to standard care.

METHODS

Post-hoc analysis stratifying patient outcomes by sex of a 48-week, multicentre, randomised controlled clinical trial comparing a biomarker-defined treatment algorithm with standard care. The primary outcome was the proportion of patients with a reduction in corticosteroid treatment (inhaled (ICS) and oral (OCS) corticosteroids). Secondary outcomes included exacerbation rates, hospital admissions and lung function.

RESULTS

Of 301 patients randomised; 194 (64.5%) were females and 107 (35.5%) were males. The biomarker algorithm led to a greater proportion of females being on a lower corticosteroid dose vs standard care which was not seen in males (effects estimate females: 3.57, 95% CI: 1.14, 11.18 vs. males 0.54, 95% CI: 0.16, 1.80). In T2-biomarker low females, reducing corticosteroid dose was not associated with increased exacerbations. Females scored higher in all ACQ-7 domains, but with no difference when adjusted for BMI/ anxiety and/or depression. Dissociation between symptoms and T2-biomarkers were noted in both sexes, with a higher proportion of females being symptom high/T2-biomarker low (22.8% vs. 15.6%; p=0.0002), whereas males were symptom low/T2-biomarker high (11.4% vs. 22.3%; p<0.0001).

CONCLUSION

This exploratory post-hoc analysis identified females achieved a greater benefit from biomarker-directed corticosteroid optimisation versus symptom-directed treatment.

Omalizumab treats chronic rhinosinusitis with nasal polyps and asthma together-a real life study

INTRODUCTION

Chronic rhinosinusitis with nasal polyps (CRSwNP) and asthma often coexist and thus treating both with one intervention is an attractive strategy.

OBJECTIVE

To prospectively evaluate whether treatment with the monoclonal antibody against IgE Omalizumab for severe allergic asthma also effectively treats co-existent CRSwNP.

METHODS

SNOT-22 and the ACQ-7 scores were recorded at 4 and 16 weeks of treatment in a cohort of patients with both CRSwNP and severe refractory allergic asthma treated with Omalizumab (n=13) according to UK guidelines for their severe asthma. SNOT-22 in a surgery only treated CRSwNP with asthma group (n=24) was compared.

RESULTS

Rapid improvement was seen at 4 weeks and 16 weeks of treatment in both CRSwNP and asthma control. The improvement in CRSwNP with Omalizumab was similar to that seen in a group of patients who received upper airway surgery.

CONCLUSION

Omalizumab treatment for severe allergic asthma also improves co-existent CRSwNP. Further clinical studies of current and emerging biological agents for severe asthma should include upper airway outcomes. These agents may be effective for severe CRSwNP and comparative studies with surgery are warranted.

Omalizumab treats chronic rhinosinusitis with nasal polyps and asthma together-a real life study

INTRODUCTION

Chronic rhinosinusitis with nasal polyps (CRSwNP) and asthma often coexist and thus treating both with one intervention is an attractive strategy.

OBJECTIVE

To prospectively evaluate whether treatment with the monoclonal antibody against IgE Omalizumab for severe allergic asthma also effectively treats co-existent CRSwNP.

METHODS

SNOT-22 and the ACQ-7 scores were recorded at 4 and 16 weeks of treatment in a cohort of patients with both CRSwNP and severe refractory allergic asthma treated with Omalizumab (n=13) according to UK guidelines for their severe asthma. SNOT-22 in a surgery only treated CRSwNP with asthma group (n=24) was compared.

RESULTS

Rapid improvement was seen at 4 weeks and 16 weeks of treatment in both CRSwNP and asthma control. The improvement in CRSwNP with Omalizumab was similar to that seen in a group of patients who received upper airway surgery.

CONCLUSION

Omalizumab treatment for severe allergic asthma also improves co-existent CRSwNP. Further clinical studies of current and emerging biological agents for severe asthma should include upper airway outcomes. These agents may be effective for severe CRSwNP and comparative studies with surgery are warranted.

Genetics of monoamine oxidase

Evidence for the genetic control of human MAO is now well established. The relationships of MAO activities to neuropsychiatric disorders or response to psychopharmacologic treatments are relatively unstudied. Preliminary findings from our own studies suggest that (1) blood MAO activity is a polygenically controlled trait; (2) there may be a subgroup of depressed patients with high MAO activity who are more severe symptomatically and more resistant to treatment, and (3) that men with atypical and mixed depressions respond more favorably than women to treatment with an MAO inhibitory drug.

Depigmented-polymerized mixed grass/birch pollen extract immunotherapy is effective in polysensitized patients

BACKGROUND

Although many patients with allergic rhinoconjunctivitis have symptoms due to sensitization with more than one pollen allergen, and mixed pollen extracts are widely used for allergen immunotherapy in practice, there are few published trials.

METHODS

We performed a 2-year multicentre, double-blind, placebo-controlled trial of subcutaneous immunotherapy with mixed depigmented-polymerized birch and grass pollen extract in 285 patients with allergic rhinoconjunctivitis symptomatic during both birch and grass pollen seasons. Primary outcome was combined symptom and medication score (SMS) assessed by daily visual analogue scales (VAS). Analysis included a placebo-based analysis examining the effect of treatment only on days when placebo patients were symptomatic.

RESULTS

There was a significant reduction in median SMS for actively treated patients (median 5.70 (interquartile range 2.62-10.02) compared with 7.07 (3.47-10.71) for placebo, P = 0.0385). Rhinitis quality-of-life scores were significantly better for active compared with placebo, and other secondary endpoints were not significantly different. Placebo-based analysis showed a 33.7% reduced SMS at year 2 for active treatment compared with placebo on days when placebo patients were symptomatic. Both birch pollen- and grass pollen-specific IgG4 increased with active treatment.

CONCLUSIONS

This study shows efficacy of mixed pollen extracts for immunotherapy for patients symptomatic to both birch and grass pollen allergens. The relatively modest effect may reflect 50% dose reduction for each allergen in the mixture. It supports VAS for symptom assessment and placebo-based analysis as useful for the analysis of immunotherapy trials. The safety of modified extracts may allow study of mixed extracts without dose reduction to improve efficacy.

Sublingual immunotherapy in allergic rhinitis: indications, efficacy and safety

Sublingual immunotherapy (SLIT) is now an established treatment for allergic rhinitis. Whilst several systematic reviews have now confirmed clinical efficacy and safety, recent analysis also confirms that therapeutic benefit persists for several years after the com- pletion of SLIT. Such findings, along with the obvious ease of administration of sublingual preparations, have clearly promoted SLIT as an attractive option for treatment of allergic rhinitis resistant to medical treatment. This article reviews the development, efficacy and safety of SLIT in allergic rhinitis and the current indications for its use.

A randomized placebo-controlled trial of rush preseasonal depigmented polymerized grass pollen immunotherapy

BACKGROUND

Specific subcutaneous immunotherapy (SCIT) for seasonal rhinoconjunctivitis with unmodified allergen extracts is effective, but limited by risk of side-effects and involves treatment over 3 years. We examined a depigmented polymerized grass pollen extract for immunogenicity and for clinical efficacy in a rush preseasonal regimen.

METHODS

Depigmented polymerized grass pollen extract was tested for proliferation and cytokine production by peripheral blood mononuclear cells. A prospective, double-blind, placebo-controlled trial of 195 grass pollen allergic patients treated with preseasonal rush immunotherapy using depigmented polymerized allergenic extract of mixed grass pollen was performed over 2 years. Primary outcome was combined symptom and medication score (SMS) during the peak of the second grass pollen season. Secondary outcomes included combined score over the whole season, during the first grass pollen season, individual symptom and medication scores, quality of life, well days/hell days and responder analysis. Adverse events were classified using the EAACI scale. Grass pollen-specific IgE and IgG4 were measured before and during treatment.

RESULTS

Depigmented polymerized extract stimulated dose-dependent T-cell proliferation and cytokine production. Patients treated with preseasonal SCIT showed improved combined scores during peak season at year 2 (median 3.93, interquartile range 0.77-6.27 vs median 5.86 for placebo, 3.11-8.36, P < 0.01). Most secondary outcomes were significantly better for active treatment. Side-effects were minimal, with no grade 3 or 4 reactions.

CONCLUSIONS

Depigmented polymerized grass pollen extract is immunogenic and clinically effective in rush preseasonal SCIT. This form of immunotherapy may be an attractive option for some patients.

Activin-A: a novel critical regulator of allergic asthma

Activin-A is a pleiotropic cytokine that belongs to the TGF-β superfamily and plays an important role in fundamental biological processes, such as development and tissue repair. Growing evidence proposes a crucial role for activin-A in immune-mediated responses and associated diseases, with both enhancing and suppressive effects depending on the cell type, the cytokine micromilieu and the context of the response. Several recent studies have demonstrated a striking increase in activin-A expression in experimental models of asthma, as well as, in the asthmatic airway in humans. Importantly, a strong immunoregulatory role for activin-A in allergic airway disease, with suppression of T helper (Th) type 2 cell-driven allergic responses and protection against the development of cardinal features of the asthmatic phenotype was revealed by in vivo functional studies. Activin-A-mediated immunosuppression is associated with induction of functional allergen-specific regulatory T cells. In human asthma, although activin-A levels are increased in the airway epithelium and submucosal cells, the expression of its signalling components is markedly decreased, pointing to decreased regulation. Nevertheless, a rapid activation of the activin-A signalling pathway is observed in the airway of individuals with asthma following inhalational allergen challenge, suggestive of an inherent protective mechanism to control disease. In support, in vitro studies using human airway epithelial cells have demonstrated that endogenous activin-A suppresses the release of inflammatory mediators, while it induces epithelial repair. Collectively, compelling evidence suggests that activin-A orchestrates the regulation of key events involved in the pathogenesis of allergic asthma. The critical role of activin-A in allergic airway responses places this cytokine as an exciting new therapeutic target for asthma.

Immunotherapy with depigmented-polymerized mixed tree pollen extract: a clinical trial and responder analysis

BACKGROUND

Rhinoconjunctivitis because of tree pollen sensitization is common in Northern Europe. Specific subcutaneous immunotherapy (SCIT) is the only disease-modifying treatment, but unmodified allergen extracts carry a risk of allergic side-effects. Our objective was to examine efficacy and safety of a depigmented-polymerized mixed tree pollen extract.

METHODS

A double-blind, placebo-controlled trial of 184 tree pollen allergic adults was performed. SCIT consisted of four increasing doses at 7-day intervals, then maintenance injections every 6 weeks for 18 months. Primary outcome was combined symptom and medication score during the 2008 season. Secondary outcomes included analysis at different levels of pollen exposure and a responder analysis. Adverse events were classified using the EAACI scale. Birch pollen-specific IgE and IgG(4) were measured before and after treatment.

RESULTS

The combined symptom and medication score of actively treated patients was significantly lower than those on placebo (P < 0.04). Increased efficacy was seen at high pollen exposure (median score 2.1 for active [IQR 0.7-3.4] vs 4.2 [IQR 2.4-5.3] for placebo for days with 500 or more pollen grains per m(3) , a 50% reduction, P < 0.01). A modified responder analysis revealed 64% responders in the active and 32% in the placebo group (P < 0.01). There were 17 systemic reactions. All were mild (grade 1 or 2) and required no treatment. Serum birch-specific IgG(4) increased in the SCIT group (P < .01).

CONCLUSIONS

SCIT with depigmented- polymerized tree pollen extract was clinically effective and well tolerated. Responder analysis suggested that one-third of patients treated with immunotherapy may not respond.

Efficacy, safety, and immunological effects of a 2-year immunotherapy with Depigoid birch pollen extract: a randomized, double-blind, placebo-controlled study

BACKGROUND

Rhinoconjunctivitis due to birch pollen sensitization is common in Northern Europe. A depigmented polymerized birch pollen extract - Depigoid has been developed for immunotherapy.

OBJECTIVE

To evaluate its clinical efficacy, safety, and effects on immunological parameters.

METHODS

Sixty-one patients aged 7-69 years were included in a randomized, double-blind, placebo-controlled trial of subcutaneous immunotherapy (SCIT) using depigmented polymerized birch pollen extract. SCIT consisted of four increasing doses at 7-day intervals, followed by maintenance injections of 500 DPP (corresponding to 30 microg Bet v1 before depigmentation) at 6-week intervals for 18 months. The primary outcome was the combined symptom and medication score during the 2006 birch pollen season. The frequency of peripheral blood mononuclear cells (PBMC)producing IL-4, IL-10, IL-12, and IL-13 was assessed in a subgroup of patients by ELISPOT assay.

RESULTS

After 18 months of treatment, the median combined symptom and medication score (upper/lower quartile) of treated patients was significantly lower than those on placebo: 8.0 (5.8-10.3) and 12.6 (8.6-16.2), respectively (P=0.004). Systemic reactions occurred in 29 patients (12 active, 17 placebo), were grades 1 or 2, and none required specific treatment. After 18 months of treatment, mean serum concentrations of specific IgE increased significantly in both groups (P<0.0001) whereas serum concentrations of both specific IgG1 and IgG4 only increased significantly in the SCIT group (P=0.002) and not in the placebo group. The seasonal increase in numbers of IL-4- and IL-13-producing PBMC was blunted by immunotherapy.

CONCLUSIONS

SCIT with depigmented polymerized birch pollen extract significantly reduced symptom and medication scores when compared with the placebo, was well tolerated, and resulted in immunological changes comparable with those of native pollen extracts.

CC chemokine receptor 4 (CCR4) in human allergen-induced late nasal responses

BACKGROUND

CC Chemokine receptor 4 (CCR4) is preferentially expressed on Th2 lymphocytes. CCR4-mediated inflammation may be important in the pathology of allergic rhinitis. Disruption of CCR4 - ligand interaction may abrogate allergen-induced inflammation.

METHODS

Sixteen allergic rhinitics and six nonatopic individuals underwent both allergen and control (diluent) nasal challenges. Symptom scores and peak nasal inspiratory flow were recorded. Nasal biopsies were taken at 8 h post challenge. Sections were immunostained and examined by light or dual immunofluorescence microscopy for eosinophils, T-lymphocytes, CCR4(+)CD3(+) and CXCR3(+)CD3(+) cells and examined by in situ hybridization for CCR4, IL-4 and IFN-gamma mRNA(+) cells. Peripheral blood mononuclear cells were obtained from peripheral blood of nine normal donors and the CCR4(+)CD4(+) cells assessed for actin polymerization in response to the CCR4 ligand macrophage-derived chemokine (MDC/CCL22) and the influence of a CCR4 antagonist tested.

RESULTS

Allergic rhinitics had increased early and late phase symptoms after allergen challenge compared to diluent; nonatopics did not respond to either challenge. Eosinophils, but not total numbers of CD3(+) T cells, were increased in rhinitics following allergen challenge. In rhinitics, there was an increase in CCR4(+)CD3(+) protein-positive cells relative to CXCR3(+)CD3(+) cells; CCR4 mRNA+ cells were increased and IL-4 increased to a greater extent than IFN-gamma. CCR4(+)CD4(+) T cells responded to MDC in vitro, and this response was inhibited by the selective CCR4 antagonist.

CONCLUSION

Lymphocyte CCR4 expression is closely associated with induction of human allergen-induced late nasal responses. Blocking CCR4-ligand interaction may provide a novel therapeutic approach in allergic disease.

Depigmented and polymerised house dust mite allergoid: allergen content, induction of IgG4 and clinical response

BACKGROUND

Polymerised allergenic extracts (allergoids) are commonly used in allergen immunotherapy. Clinical efficacy and safety of these extracts have been demonstrated. Recently, allergen sequences have been identified by mass spectrometry in depigmented and polymerised (Dpg-Pol) extracts. The objectives of this study were to investigate the presence of allergens in Dpg-Pol extracts of house dust mite and to analyze the immunological changes induced by these extracts in asthmatic patients enrolled in a double-blind, placebo-controlled study.

METHODS

Dpg-Pol extracts were manufactured and vaccines with a composition of 50% Dermatophagoides pteronyssinus and 50% D. farinae (100 HEPL/ml) were prepared. Allergen composition was analyzed by mass spectrometry. Patients with asthma and rhinoconjunctivitis were treated in a 1-year, double-blind, placebo-controlled, parallel-group study with 6 up-dosing and monthly maintenance injections. Specific IgE and IgG4 titres to D. pteronyssinus, Der p 1 and Der p 2 were measured in patients' sera using the CAP system and direct ELISA experiments.

RESULTS

Sequences from the major allergens Der p 1 and Der p 2 and from other allergens were identified in native and Dpg-Pol extracts. There was a statistically significant increase in specific IgG4, a decrease in the ratio of IgE/IgG4 to D. pteronyssinus and a significant increase in specific IgG4 to Der p 1 and Der p 2 in the patients allotted to active treatment.

CONCLUSIONS

The detection of allergen sequences suggests preservation of major and minor allergens in Dpg-Pol allergoids from house dust mites. Efficacy in asthma treatment and the increase in specific IgG4 seem to be associated with the presence of major allergens in Dpg-Pol allergen extracts.

Chemokine responsiveness of CD4+ CD25+ regulatory and CD4+ CD25- T cells from atopic and nonatopic donors

BACKGROUND

Allergic inflammation is associated with Th2-type T cells, which can be suppressed by CD4+ CD25+ regulatory T cells (Tregs). Both express chemokine receptors (CCR) 4 and CCR8, but the dynamics of expression and effect of atopic status are unknown.

OBJECTIVE

To examine the expression of chemokine receptors by CD4+ CD25+ and CD4+ CD25- T cells from atopic and nonatopic donors, and document response to allergen stimulation in vitro.

METHODS

Chemokine receptor expression was examined by flow cytometry and quantitative PCR of CD4+ CD25hi and CD4+ CD25- T cells from atopics and nonatopics. Responsiveness to chemokines was by actin polymerization. Dynamics of chemokine receptor expression in 6-day allergen-stimulated cultures was analysed by carboxyfluoroscein succinimidyl ester labelling.

RESULTS

CD4+ CD25hi Tregs preferentially expressed CCR3, CCR4, CCR5, CCR6 and CCR8. CD4+ CD25hi Tregs responded to the chemokine ligands for CCR4, CCR6 and CCR8 (CCL17, 22, 20 and 1 respectively), with no differences between atopic and nonatopic donors. Over 6-day allergen stimulation, CD4+ CD25+ T-cells downregulated CCR4 and upregulated CCR7, in contrast to CD4+ CD25- effector cells, which downregulated CCR7 and upregulated CCR4.

CONCLUSIONS

CCR4, CCR6 and CCR8 have potential roles in localization of both CD4+ CD25+ regulatory and CD4+ CD25- effector T cells to sites of allergic inflammation. Upregulation of CCR7 and downregulation of CCR4 upon allergen stimulation of Tregs may allow their recirculation from sites of inflammation, in contrast to retention of effector T cells.

Regulatory T cells and asthma

Airway inflammation in asthma is characterized by activation of T helper type-2 (Th2) T cells, IgE production and eosinophilia. In many cases, this process is related to an inappropriate T cell response to environmental allergens, and other T cell-dependent pathways may also be involved (such as Th17). Regulatory T cells (Tregs) are T cells that suppress potentially harmful immune responses. Two major subsets of Treg are CD25(hi), Foxp3(+)Tregs and IL-10-producing Tregs. There is evidence that the numbers or function of both subsets may be deficient in patients with atopic allergic disease. Recent work has extended these findings into the airway in asthma where Foxp3 expression was reduced and CD25(hi) Treg-suppressive function was deficient. In animal models of allergic airways disease, Tregs can suppress established airway inflammation and airway hyperresponsiveness, and protocols to enhance the development, recruitment and function of Tregs have been described. Together with studies of patients and in vitro studies of human T cells, these investigations are defining potential interventions to enhance Treg function in the airway in asthma. Existing therapies including corticosteroids and allergen immunotherapy act on Tregs, in part to increase IL-10 production, while vitamin D3 and long-acting beta-agonists enhance IL-10 Treg function. Other possibilities may be enhancement of Treg function via histamine or prostanoid receptors, or by blocking pro-inflammatory pathways that prevent suppression by Tregs (activation of Toll-like receptors, or production of cytokines such as IL-6 and TNF-alpha). As Tregs can also suppress the potentially beneficial immune response important for controlling infections and cancer, a therapeutic intervention should target allergen- or site-specific regulation.

Detection of allergen composition and in vivo immunogenicity of depigmented allergoids of Betula alba

BACKGROUND

Chemical modification of allergen vaccines to reduce IgE binding improves safety while maintaining clinical efficacy. However, this also complicates the characterization of allergoids using techniques as for native allergen extracts.

OBJECTIVES

The objective of this study was to analyse the molecular size of Betula alba depigmented allergoids, conservation of major allergens in the allergoids and in vivo antibody response to immunization.

METHODS

The molecular size of depigmented allergoids was evaluated by high performance-size exclusion chromatography and light scattering techniques. Protein composition was compared with native extracts by capillary liquid chromatography-tandem mass spectrometry based peptide mapping. Rabbits were immunized with depigmented allergoid of Betula pollen adsorbed onto aluminium hydroxide (Depigoid). IgG antibodies against individual allergens were determined by ELISA and immunoblot.

RESULTS

Depigmented allergoids contained a range of high molecular weight particles, approximately 60% of which had a molecular weight of 1-3 MDa. Peptide sequencing confirmed the preservation of five isoforms of Bet v 1, as well as Bet v 2, Bet v 6 and Bet v 7. Sera from immunized rabbits showed high levels of specific IgG to rBet v 1.0101 and rBet v 2.

CONCLUSIONS

The mean protein content was 544+/-106 microg per mg of freeze-dried material for depigmented allergoids and 434+/-71 for native extracts. They retain the capacity to induce specific IgG antibodies against individual allergens present in the native extract. These findings confirm the immunogenicity of depigmented allergoids and may explain why patients treated with these vaccines are protected against the native allergens. Analysis of molecular size and allergen content may be useful techniques for characterization and standardization of allergoid products.

Effect of inhaled interleukin-5 on eosinophil progenitors in the bronchi and bone marrow of asthmatic and non-asthmatic volunteers

BACKGROUND

Asthma is characterized by increases in mature eosinophils and their progenitors within the bronchus and bone marrow. IL-5 plays a key role in eosinophil development in the bone marrow and at the site of allergic inflammation. We therefore studied the effects of nebulized IL-5 on eosinophils, their progenitors and in situ haemopoiesis within the airway and bone marrow.

METHODS

Nine atopic asthmatics and 10 non-atopic non-asthmatic control volunteers inhaled 10 microg of IL-5 or placebo via a nebulizer in a double-blind, randomized, cross-over study. Bronchoscopy, bone marrow aspiration and peripheral blood sampling were performed 24 h after nebulization. Four weeks later, volunteers inhaled the alternative solution and underwent a repeat bronchoscopy and bone marrow aspiration.

RESULTS

Inhalation of IL-5 significantly decreased CD34(+)/IL-5Ralpha mRNA(+) cells within the bronchial mucosa and the percentage of CD34(+) cells that were CCR3(+) within the bone marrow of atopic asthmatic, but not control, volunteers. Inhalation of IL-5 also induced a significant increase in bronchial mucosal eosinophils in the non-atopic non-asthmatic control volunteers, but not in the asthmatics. IL-5 had no effect on spirometry or airways hyper-reactivity in either group.

CONCLUSIONS

Inhaled IL-5 modulated eosinophil progenitor numbers in both the airways and bone marrow of asthmatics and induced local eosinophilia in non-asthmatics.

Allergen-induced airway remodelling

Airway remodelling is associated with chronic asthma but it remains unclear whether it results from airway inflammation in response to allergens or immune-mediated events such as viral infections. Although the acute inflammation associated with asthma has been modelled extensively both in vitro and in vivo, the structural changes occurring in the lung have only recently been investigated. These in vitro, in vivo and in silico systems have been designed to examine the pathways leading to allergen-induced airway remodelling and have enabled investigators to draw conclusions about the participation of key cells and molecules in the development of allergen-induced airway remodelling. However, fundamental questions remain regarding the genesis of remodelling as well as the relationship between functional symptoms and pathological changes that occur. In this review the key questions relating allergen exposure to development of remodelling are discussed, as well as the steps that are being undertaken to investigate them.

How is difficult asthma managed?

Most patients with asthma can be easily treated. Some have difficult asthma; in some because the diagnosis is erroneous, in others because of comorbidity or noncompliance. A European Respiratory Society Task Force has called for an integrated approach for these patients, and positive results have been reported using protocols. In the UK, there is no overall understanding of the size of this problem, or how these patients are managed. A postal survey of 683 consultant members of the British Thoracic Society designed to elicit respondents' views on how they would manage four clinical scenarios was conducted. There was a 50.4% response rate. Few reported a uniform approach to the investigation of such patients. The availability of allied healthcare professionals was variable. The 21 consultant respiratory physicans, reporting a special interest in difficult asthma, were significantly more likely to objectively assess compliance, perform skin-prick tests and to utilise a liaison psychiatrist than those without an expressed special interest in asthma. Many reported difficulty in accessing psychologists, liaison psychiatrists and social workers. Approaches to the diagnosis and management of "vocal cord dysfunction" were variable. The results of this postal survey of specialist thoracic physicians in the UK suggest that a protocol for difficult asthma is not in widespread use and that access to necessary allied healthcare professionals is not uniform. Pulmonologists with a declared special interest in difficult asthma may have configured their services and approaches more in line with that proposed by the European Respiratory Society Task Force.

In situ high-energy x-ray diffraction study of the local structure of supercooled liquid Si

Employing the technique of electrostatic levitation, coupled with high-energy x-ray diffraction and rapid data acquisition methods, we have obtained high quality structural data more deeply into the supercooled regime of liquid silicon than has been possible before. No change in coordination number is observed in this temperature region, calling into question previous experimental claims of structural evidence for the existence of a liquid-liquid phase transition.

Cat allergen peptide immunotherapy reduces CD4(+) T cell responses to cat allergen but does not alter suppression by CD4(+) CD25(+) T cells: a double-blind placebo-controlled study

BACKGROUND

We have previously described both modification of allergen immunotherapy using peptide fragments, and reduced regulation of allergen stimulated T cells by CD4(+) CD25(+) T cells from allergic donors when compared with nonallergic controls. It has been suggested that allergen immunotherapy induces regulatory T cell activity: we hypothesized that allergen peptide immunotherapy might increase suppressive activity of CD4(+) CD25(+) T cells.

OBJECTIVE

To examine cat allergen-stimulated CD4 T cell responses and their suppression by CD4(+) CD25(+) T cells before and after cat allergen peptide immunotherapy in a double-blind placebo-controlled study.

METHODS

Peripheral blood was obtained and stored before and after peptide immunotherapy or placebo treatment. CD4(+) and CD4(+) CD25(+) were then isolated by immunomagnetic beads and cultured with allergen in vitro.

RESULTS

Comparing cells from blood taken before with that after peptide immunotherapy there was a significant reduction in both proliferation and IL-13 production by allergen-stimulated CD4+ T cells, whereas no change was seen after placebo. CD4(+) CD25(+) T cells suppressed both proliferation and IL-13 production by CD4(+) CD25(-) T cells before and after therapy but peptide therapy was not associated with any change in suppressive activity of these cells.

CONCLUSION

Allergen peptide immunotherapy alters T cell response to allergen through mechanisms other than changes in CD4(+) CD25(+) T cell suppression.

Difference in icosahedral short-range order in early and late transition metal liquids

New short-range order data are presented for equilibrium and undercooled liquids of Ti and Ni. These were obtained from in situ synchrotron x-ray diffraction measurements of electrostatically levitated droplets. While the short-range order of liquid Ni is icosahedral, consistent with Frank's hypothesis, significantly distorted icosahedral order is observed in liquid Ti. This is the first experimental observation of distorted icosahedral short-range order in any liquid, although this has been predicted by theoretical studies on atomic clusters.

Systematic assessment of difficult-to-treat asthma

Five per cent of asthmatics remain symptomatic despite high-dose treatment. The aim of the study was to investigate how often such difficult-to-treat asthma is due to intractable asthma, misdiagnosis, non-adherence with therapy, or psychiatric problems. Difficult asthma was defined as persistence of symptoms despite treatment at step 4 of British guidelines or requirement for long-term oral glucocorticoids (step 5). One-hundred patients with a respiratory physician diagnosis of asthma were investigated in a single tertiary respiratory unit in an open and descriptive study. Twelve of the patients studied did not have asthma and a further seven had additional diagnoses. Of the remainder, 55 had an asthma diagnosis confirmed by demonstration of reversible airflow narrowing or peak flow variability, whilst 20 did not. Non-compliance with prednisolone therapy was more frequent in the 55 with confirmed asthma (nine of 18 prescribed oral prednisolone at a dose of > or = 15 mg x day(-1)) and was not detected in the "unconfirmed asthma" group. There were no other significant differences between these groups. A major psychiatric component was detected in 10 patients. Systematic evaluation of difficult asthma is useful as it can identify alternative or additional diagnoses, psychiatric illness or nonconcordance with therapy in a substantial proportion of cases (32% in the present series).

First x-ray scattering studies on electrostatically levitated metallic liquids: demonstrated influence of local icosahedral order on the nucleation barrier

To explain the unusual stability of undercooled liquids against crystallization, Frank hypothesized that the local structures of undercooled liquids contain a significant degree of icosahedral short-range order, which is incompatible with long-range periodicity. We present here the first direct experimental demonstration of Frank's complete hypothesis, showing a correlation between the nucleation barrier and a growing icosahedral short-range order with decreasing temperature in a Ti39.5Zr39.5Ni21 liquid. A new experimental facility, BESL (Beamline Electrostatic Levitation), was developed to enable the synchrotron x-ray structural studies on deeply undercooled, reactive liquids.

Elevated expression of interleukin-9 mRNA in the bronchial mucosa of atopic asthmatics and allergen-induced cutaneous late-phase reaction: relationships to eosinophils, mast cells and T lymphocytes

BACKGROUND

Interleukin-9 is a T cell-derived Th2-type cytokine that has been linked to airway hyper-responsiveness, mucus hypersecretion and mast cell infiltration in animal models. We recently demonstrated the potential for IL-9 to act in human eosinophil development and survival.

OBJECTIVES

The aims of this study were: (i) to compare IL-9 mRNA expression in bronchial biopsies between atopic asthmatics and normal controls, (ii) to investigate kinetic expression of IL-9 mRNA in skin biopsies after allergen challenge; and (iii) to relate IL-9 expression to infiltration of eosinophils, mast cell and T lymphocytes in local tissue.

METHODS

Bronchial biopsies were obtained from atopic asthmatics (n = 12) and normal non-asthmatics (n = 12) at baseline. Skin biopsies were obtained from atopic subjects (n = 11) at 1, 3, 6, 24, 48 and 72 h after allergen challenge. Diluent challenge sites at 24 h were used as controls. IL-9 mRNA was identified using the technique of in situ hybridization. The numbers of eosinophils, mast cells and T cells were evaluated by immunohistochemistry.

RESULTS

The numbers of IL-9 mRNA(+) cells present in the bronchial mucosa were significantly greater in atopic asthmatics than those in normal controls (P = 0.003). The numbers of eosinophils, but not mast cells, were also significantly higher in asthmatics (P < 0.005). The numbers of IL-9 mRNA(+) cells present in the airway of asthmatics significantly correlated with the numbers of eosinophils (r = 0.623, P = 0.03), but not mast cells or T cells. Compared with diluent challenge, the numbers of IL-9 mRNA(+) cells were significantly elevated at all allergen-challenged sites in the skin, with maximal signals at 48 h (P < 0.005). At 72 h, the numbers of IL-9 mRNA(+) cells significantly correlated with the numbers of eosinophils (r = 0.707, P = 0.015).

CONCLUSION

Elevated expression of IL-9 in allergic inflammation may contribute to local eosinophil infiltration and survival in asthma and other allergic atopic diseases.

Neoadjuvant therapy for esophageal cancer: standard of care or elusive myth?

Although surgical resection as the sole treatment modality for esophageal carcinoma has historically been associated with poor survival rates, improvements have recently been reported using varied neoadjuvant chemo-radiation protocols. This study evaluates the outcome of patients undergoing surgery for esophageal carcinoma at the University of Miami/Jackson Memorial Hospital between July 1991 and June 1996. Seventy-two patients underwent esophageal resection; 51 males and 21 females with a median age of 62.5 years (range = 42-82). Histology was equally distributed between adenocarcinoma (36 patients; 50%) and squamous cell carcinoma (36 patients; 50%). Pathological stage distribution consisted of 6 stage 0 (8%), 10 stage I (14%), 23 stage II (32%), 31 stage III (43%), and 2 stage IV (3%) lesions. Patients were divided into three groups according to the type of preoperative treatment; Group 1 (n = 44); surgery alone; Group 2 (n = 18); neoadjuvant 5-fluorouracil based chemotherapy, and Group 3 (n = 9); neoadjuvant 5-fluorouracil based chemotherapy in conjunction with external beam radiation (XRT). One patient received preoperative XRT alone. All survivors were followed for a minimum of 1 year and statistical analysis was performed using Kaplan-Meier curves, log-rank, and chi-square tests. In the 28 patients receiving any form of neoadjuvant therapy only one patient had a pathological complete response (CR) (3.5%). The overall 5 year and median survival rates were 18 per cent and 20.5 months (range = 0-73), respectively. Individual treatment group survival rates at 5 years were 28% for Group 1; 21% for Group 2; and 0% for Group 3, showing no survival difference between Groups 1 and 2; Group 3 fared significantly worse than the other two, probably as a result of the high operative mortality in this group. These results indicate that surgical resection continues to be an important treatment modality for esophageal carcinoma. Neoadjuvant chemotherapy in our experience failed to improve these survival rates and pre-operative chemoradiation was associated with a high perioperative mortality rate. Chemotherapy regimens with higher CRs may further improve these survival rates.

Late asthmatic reactions provoked by intradermal injection of T-cell peptide epitopes are not associated with bronchial mucosal infiltration of eosinophils or T(H)2-type cells or with elevated concentrations of histamine or eicosanoids in bronchoalveolar fluid

BACKGROUND

Isolated late asthmatic reactions can be provoked by intradermal challenge of allergen-derived T-cell peptide epitopes.

OBJECTIVE

The purpose of this study was to determine whether the isolated LAR is associated with the local accumulation of inflammatory cells, the expression of T(H)2 cytokines, and the production of pharmacologic mediators.

METHODS

A randomized, placebo-controlled, crossover study design was used. The investigation involved bronchial and skin biopsies and bronchoalveolar lavage (BAL) fluids from 8 cat-allergic subjects who developed significant late asthmatic reactions 6 hours after intradermal injection of Fel d 1 chain 1-derived peptides (FC1Ps).

RESULTS

Immunostaining of bronchial biopsy specimens showed no changes in the numbers of eosinophils, neutrophils, basophils, mast cells, CD3(+), CD4(+) or CD8(+) T cells, CD25(+) cells or macrophages, or cells mRNA(+) for IL-4, IL-5, or IL-13 when the FC1P day was compared with the diluent control day. There were also no significant differences in eosinophil numbers, either in BAL fluids or in peripheral blood after FC1P challenge. Furthermore, there were no significant alterations in the concentrations of histamine, histamine-releasing factors, or eicosanoids (LTC(4)/D(4)/E(4), PGD(2), PGE(2), TXB(2), PGF(2alpha)) in BAL fluids. FC1Ps induced a significant (P <.05) elevation in CD8(+) cells in the skin and an unexpected decrease in IL-5 in BAL fluids (P =.043).

CONCLUSION

Part of the asthma process might involve T cell-dependent airway narrowing with no requirement for IgE, mast cells, or infiltrating inflammatory cells.

Addition of leukotriene antagonists to therapy in chronic persistent asthma: a randomised double-blind placebo-controlled trial

BACKGROUND

Controlled trials suggest that leukotriene receptor antagonists can improve lung function and reduce requirement for oral or inhaled corticosteroids in patients with asthma. We aimed to assess whether montelukast, a leukotriene receptor antagonist, can improve symptoms or lung function in patients with chronic asthma with symptoms already taking corticosteroids.

METHODS

We did a double-blind, placebo-controlled, crossover, randomised add-on study in which 100 patients with asthma and symptoms despite treatment with inhaled corticosteroids and additional therapy were given 10 mg montelukast sodium for 14 days in an outpatient clinic setting. Outcome measures were symptoms and peak flow diaries.

FINDINGS

72 patients had diary data for analysis. Compared with placebo, addition of montelukast did not result in any significant change in symptom scores (mean difference between the last 7 days of each treatment period 0.05; 95% CI --0.86 to 1.14), rescue inhaled beta(2) agonist use (mean difference in puffs per day 0.41; -0.29 to 0.57), or twice daily peak expiratory flow (PEF) measurements (mean difference in morning PEF 1.18 L/min; -14.29 to 17.14), and mean difference in evening peak flow (-0.50; -17.42 to 12.86). When treatment response was defined as a 15% or greater increase in mean peak flow readings, there were four responders to montelukast and seven responders to placebo.

INTERPRETATION

Based on PEF data from our previous studies of a similar patient group we would have expected to detect changes of more than 5%. Used as additional therapy in a hospital outpatient clinic setting, montelukast did not provide such additional benefit in patients with moderate or severe asthma.

A thousand points of light or just dim bulbs? Radiolabeled antibodies and colorectal cancer imaging

Radioimmunoscintigraphy (RIS) is coming into its own as an imaging modality in clinical oncology. Early experience with indium-111-labeled intact murine monoclonal antibodies (MoAbs) in colorectal cancer suggested that RIS images hepatic metastases poorly. Moreover, an antimurine immune response was frequently provoked, precluding multiple follow-up RIS studies in individual patients due to reticuloendothelial sequestration of the radioimmunoconjugate before tumor targeting could occur. Recent trials of technetium-99m-labeled antibody fragments and human MoAbs have demonstrated significant improvement in imaging efficacy, and repeated or serial imaging is possible because of the absence of associated immunogenicity. RIS is demonstrably more sensitive than conventional diagnostic modalities (CDM) such as computed tomography (CT) for detection of extrahepatic abdominal and pelvic colorectal carcinoma and is complementary to CDM in imaging liver metastases. In a surgical decision-making analysis comparing CT, RIS (IMMU-4 99mTc-Fab'; CEA-Scan), and CT plus RIS in patients with recurrent or metastatic colorectal cancer, CT plus RIS improved correct prediction of resectability by 40% and correct prediction of unresectability by 100% compared with CT alone. At the present time, RIS used in combination with CDM contributes an incremental improvement in diagnostic accuracy in colorectal cancer patients with known or suspected recurrent disease. Basic and clinical research currently in progress promises to yield agents and methods that provide rapid high-resolution imaging, high tumor-to-background ratios in all organs at risk for tumor recurrence or metastasis, negligible immunogenicity and toxicity, and a significant further improvement in the accuracy of clinical decision making in oncology patients.

Postmastectomy radiotherapy: clinical practice guidelines of the American Society of Clinical Oncology

OBJECTIVE

To determine indications for the use of postmastectomy radiotherapy (PMRT) for patients with invasive breast cancer with involved axillary lymph nodes or locally advanced disease who receive systemic therapy. These guidelines are intended for use in the care of patients outside of clinical trials.

POTENTIAL INTERVENTION

The benefits and risks of PMRT in such patients, as well as subgroups of these patients, were considered. The details of the PMRT technique were also evaluated.

OUTCOMES

The outcomes considered included freedom from local-regional recurrence, survival (disease-free and overall), and long-term toxicity.

EVIDENCE

An expert multidisciplinary panel reviewed pertinent information from the published literature through July 2000; certain investigators were contacted for more recent and, in some cases, unpublished information. A computerized search was performed of MEDLINE data; directed searches based on the bibliographies of primary articles were also performed.

VALUES

Levels of evidence and guideline grades were assigned by the Panel using standard criteria. A "recommendation" was made when level I or II evidence was available and there was consensus as to its meaning. A "suggestion" was made based on level III, IV, or V evidence and there was consensus as to its meaning. Areas of clinical importance were pointed out where guidelines could not be formulated due to insufficient evidence or lack of consensus.

RECOMMENDATIONS

The recommendations, suggestions, and expert opinions of the Panel are described in this article.

VALIDATION

Seven outside reviewers, the American Society of Clinical Oncology (ASCO) Health Services Research Committee members, and the ASCO Board of Directors reviewed this document.

Mechanisms of T cell peptide epitope-dependent late asthmatic reactions

Short peptide sequences corresponding to T cell epitopes have been identified in the major cat allergen Fel d 1. In order to directly activate allergen-specific T cells in cat-allergic asthmatic individuals, peptides were administered by intradermal injection. Subsequently, a proportion of subjects experienced a delayed reduction of airway calibre manifested as a decrease in FEV(1). Changes in lung function occurred approximately 3 h after peptide injection, peaked at 6 h and resembled an isolated late asthmatic reaction (LAR). Using molecular tissue typing techniques, it was determined that many of the individuals experiencing isolated LAR expressed particular HLA-DR molecules. These molecules were shown in subsequent experiments to bind individual peptides within the preparation and thus to activate T cells in a major histocompatibility complex (MHC)-restricted fashion. The precise mechanisms whereby MHC-restricted activation of allergen-specific T cells gives rise to bronchoconstriction are currently under investigation.

Expression of eotaxin in induced sputum of atopic and nonatopic asthmatics

BACKGROUND

The chemokine eotaxin has been implicated in airway eosinophilia in atopic asthma. We have compared airway eosinophils and eotaxin expression in induced sputum from well-matched atopic and nonatopic asthmatics.

METHODS

Eosinophil numbers, eosinophil cationic protein (ECP), and the expression of eotaxin were examined in induced sputum from atopic asthmatics (AA = 11), nonatopic asthmatics (NAA = 11), and atopic (AC = 12) and normal (NC = 10) controls. Slides were prepared for differential cell counts by Romanowsky stain, and ECP levels were measured by RIA. Eotaxin expression was detected by in situ hybridization, with 35S-labelled riboprobes and immunocytochemistry.

RESULTS

The numbers of eosinophils and ECP concentration were increased in the sputum of AA and NAA compared with AC and NC (P < 0.05). The numbers of eotaxin mRNA+ and immunoreactive cells were increased in NAA, but not AA, when compared with controls (P < 0.05). Eotaxin immunoreactive cells in NAA were significantly higher than in AA (P < 0.05). Eotaxin was expressed predominantly by macrophages, eosinophils, and epithelial cells. In NAA, but not AA, the numbers of eotaxin mRNA+ cells were correlated with histamine PC20 (r = -0.81, P < 0.01) and eosinophil numbers in sputum (r = 0.7, P < 0.05).

CONCLUSIONS

Eotaxin production by macrophages, eosinophils, and epithelial cells may play a more pronounced role in airway eosinophilia in nonatopic than in atopic asthma.

Macrophage subpopulations and macrophage-derived cytokines in sputum of atopic and nonatopic asthmatic subjects and atopic and normal control subjects

BACKGROUND

Previous studies have shown a prominent macrophage signal in the bronchial mucosa from nonatopic (intrinsic) compared with atopic (extrinsic) asthmatic subjects. This observation might have represented an expansion of a proinflammatory macrophage population or a homeostatic mechanism to decrease T(H)2-type inflammation.

OBJECTIVE

The aim of the study was to investigate the numbers of macrophages and macrophage subpopulations and the expression of IL-10 and IL-12 in sputum from asthmatic and control subjects.

METHODS

Eight atopic asthmatic (AA) subjects, 10 nonatopic asthmatic (NAA) subjects, 6 atopic control (AC) subjects, and 7 normal control (NC) subjects underwent sputum induction. Macrophages were enumerated by using Romanowsky stain and immunocytochemistry (CD68). RFD1 (interdigitating cell marker) and RFD7 (mature phagocyte marker) mAbs were used for immunocytochemical phenotyping, whereas IL-10 and IL-12 messenger (m)RNA was examined with in situ hybridization by using (35)S-labeled riboprobes. The phenotype of cells expressing IL-10 or IL-12 mRNA was examined by simultaneous in situ hybridization and immunostaining.

RESULTS

No differences in the numbers of CD68(+) macrophages and RFD1(+), RFD7(+), and RFD1(+)/RFD7(+) subpopulations were found between AA, NAA, AC, and NC subjects. However, the numbers of IL-10 and IL-12 mRNA(+) cells were increased in AA subjects compared with NAA, AC, and NC subjects (P <.05). No other differences were found among the groups. Most of the IL-10 and IL-12 mRNA(+) cells in sputum from asthmatic subjects were macrophages (>80%), with less than 10% of mRNA colocalizing to epithelial cells.

CONCLUSIONS

Sputum macrophage numbers, unlike tissue macrophages, as previously reported, were not elevated in NAA subjects. Increased IL-10 and IL-12 expression in atopic asthma may indicate the existence of a homeostatic mechanism to decrease lung inflammation. The lack of such cytokines in intrinsic asthma may predispose to bronchial inflammation in these subjects.

Internal hemipelvectomy for solitary pelvic thyroid cancer metastases

BACKGROUND AND OBJECTIVES

Radioactive iodine (RAI) therapy remains a primary treatment modality for metastatic thyroid carcinoma, but poor tumor uptake of the agent can limit its usefulness. While offering effective palliation, radiation therapy is not curative, and chemotherapy is even less useful. Surgical resection occasionally remains the only hope of offering a long-term cure in the case of isolated metastases.

METHODS

We describe 3 cases of thyroid cancer metastatic to the pelvic girdle that were unresponsive to RAI and other nonoperative therapies, which presented over a 15-year time period. The pelvic disease was the only site of active disease in all cases, and all 3 patients were suffering considerable pain. All 3 patients underwent internal hemipelvectomy with reconstruction in 2 cases using a pelvic bone allograft.

RESULTS

All 3 experienced symptomatic relief and early mobilization. While the infection rate was 100%, these all responded completely to operative debridement, irrigation, and antibiotics. One patient, found postoperatively to have a positive surgical margin, developed a local recurrence at 4 months and died. A second patient developed a local recurrence at 11 months and died. The third patient underwent a revision of her hip arthroplasty because of acetabular loosening after a fall 21 months postoperatively. She is alive, disease-free, and ambulatory with the aid of a cane 32 months after the original procedure.

CONCLUSIONS

We propose this surgical procedure in selected patients with metastatic pelvic thyroid cancer. It provides symptomatic relief with a chance for prolonged disease-free survival some patients.

In situ temperature measurements with thermocouple probes during laser interstitial thermotherapy (LITT): quantification and correction of a measurement artifact

BACKGROUND AND OBJECTIVE

The purpose of this work was to quantify the magnitude of an artifact induced by stainless steel thermocouple probes in temperature measurements made in situ during experimental laser interstitial thermo-therapy (LITT). A procedure for correction of this observational error is outlined.

STUDY DESIGN/MATERIALS AND METHODS

A CW Nd:YAG laser system emitting 20W for 25-30 s delivered through a fiber-optic probe was used to create localized heating. The temperature field around the fiber-optic probe during laser irradiation was measured every 0.3 s in air, water, 0.4% intralipid solution, and fatty cadaver pig tissue, with a field of up to fifteen needle thermocouple probes.

RESULTS

Direct absorption of Nd:YAG laser radiation by the thermocouple probes induced an overestimation of the temperature, ranging from 1.8 degrees C to 118.6 degrees C in air, 2.2 degrees C to 9.9 degrees C in water, 0.7 C to 4.7 C in intralipid and 0.3 C to 17.9 C in porcine tissue after irradiation at 20W for 30 s and depending on the thermocouple location. The artifact in porcine tissue was removed by applying exponential and linear fits to the measured temperature curves.

CONCLUSION

Light absorption by thermocouple probes can induce a significant artifact in the measurement of laser-induced temperature increases. When the time constant of the thermocouple effect is much smaller than the thermal relaxation time of the surrounding tissue, the artifact can be accurately quantified. During LITT experiments where temperature differences of a few degrees are significant, the thermocouple artifact must be removed in order to be able accurately to predict the treatment outcome.