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1.
Allergy ; 66(9): 1142-51, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21645010

ABSTRACT

Airway remodeling is a central feature of asthma. It is exemplified by thickening of the lamina reticularis and structural changes to the epithelium, submucosa, smooth muscle, and vasculature of the airway wall. Airway remodeling may result from persistent airway inflammation. Immunoglobulin E (IgE) is an important mediator of allergic reactions and has a central role in airway inflammation and asthma-related symptoms. Anti-IgE therapies (such as omalizumab) have the potential to block an early step in the allergic cascade and therefore have the potential to reduce airway remodeling. The reduction in free IgE levels following anti-IgE therapy leads to reductions in high-affinity IgE receptor (FcεRI) expression on mast cells, basophils, and dendritic cells. This combined effect results in attenuation of several markers of inflammation, including peripheral and bronchial tissue eosinophilia and levels of granulocyte macrophage colony-stimulating factor, interleukin (IL)-2, IL-4, IL-5, and IL-13. Considering the previously demonstrated anti-inflammatory effects of anti-IgE therapy, along with results from a small study showing continued benefit after discontinuation of long-term treatment, a larger study to assess its effect on markers of airway remodeling is underway.


Subject(s)
Airway Remodeling/drug effects , Antibodies, Anti-Idiotypic/therapeutic use , Asthma/drug therapy , Animals , Antibodies, Anti-Idiotypic/adverse effects , Asthma/immunology , Asthma/pathology , Humans , Hypersensitivity/immunology
2.
Curr Mol Med ; 11(7): 599-608, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21707512

ABSTRACT

The prevalence of asthma and costs of its care have been continuously increasing, but novel therapeutic options to treat this inflammatory disease have not been brought to the US market. Current therapies such as inhaled steroids, long-acting beta-agonist bronchodilators, antihistamines and immunomodulators may control the symptoms of allergic asthma but fail to modify the underlying disease. Excessive use of steroids and other immunosuppresents alter the patient's quality of life, produce undesirable toxicities, and increase the risk of other pathologies such as diabetes. Hence novel therapeutic options to manage asthma are desirable. In the present review, we have discussed the role of the polyol pathway enzyme aldose reductase (AR) in the amplification of allergic airway inflammation. Recent studies have indicated that AR inhibition prevents the NF-κB-dependent generation of pro-inflammatory cytokines and chemokines in mouse models of allergic airway inflammation indicating the potential use of AR inhibition as a novel tool to control allergic responses. Since orally available AR inhibitors have already undergone phase III clinical trials for diabetic neuropathy and appear to have a manageable side effects profile, they could be readily developed as potential new drugs for the treatment of asthma and related complications.


Subject(s)
Aldehyde Reductase/antagonists & inhibitors , Asthma/drug therapy , Aldehyde Reductase/metabolism , Animals , Anti-Inflammatory Agents/therapeutic use , Asthma/epidemiology , Asthma/immunology , Humans , Inflammation/drug therapy , Inflammation/immunology , Mice , NF-kappa B/metabolism , Respiratory System/enzymology , Respiratory System/immunology
3.
Eur Respir J ; 32(6): 1548-54, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18768579

ABSTRACT

The asthmatic response to the common cold is highly variable, and early characteristics that predict worsening of asthma control following a cold have not been identified. In this prospective multicentric cohort study of 413 adult subjects with asthma, the mini-Asthma Control Questionnaire (mini-ACQ) was used to quantify changes in asthma control and the Wisconsin Upper Respiratory Symptom Survey-21 (WURSS-21) to measure cold severity. Univariate and multivariable models were used to examine demographic, physiological, serological and cold-related characteristics for their relationship to changes in asthma control following a cold. Clinically significant worsening of asthma control was observed following a cold (mean+/-SD increase in mini-ACQ score of 0.69+/-0.93). Univariate analysis demonstrated that season, centre location, cold duration and cold severity measurements were all associated with a change in asthma control. Multivariable analysis of the covariates available within the first 2 days of cold onset revealed that the day 2 and cumulative sum of day 1 and 2 WURSS-21 scores were significant predictors of the subsequent changes in asthma control. In asthmatic subjects, cold severity within the first 2 days can be used to predict subsequent changes in asthma control. This information may help clinicians prevent deterioration in asthma control following a cold.


Subject(s)
Asthma/diagnosis , Asthma/physiopathology , Common Cold/complications , Adrenal Cortex Hormones/therapeutic use , Adult , Asthma/etiology , Cohort Studies , Female , Humans , Male , Middle Aged , Multivariate Analysis , Prospective Studies , Quality of Life , Risk , Surveys and Questionnaires , Treatment Outcome
4.
J Leukoc Biol ; 70(5): 730-6, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11698492

ABSTRACT

The anti-inflammatory cytokine interleukin (IL)-10 suppresses inducible nitric oxide synthase (iNOS); therefore, NO production should increase in the absence of IL-10. Production of NO (as nitrite) by bronchoalveolar lavage cells of IL-10 knockout ((-/-)) mice was assessed after ovalbumin sensitization and airway challenge (S/C) and was compared with the IL-10-sufficient, wild-type (WT) C57Bl6. Eosinophil recruitment occurred in S/C WT and IL-10(-/-) mice, suggesting allergic airway inflammation. Alveolar macrophages (per g mouse) were unchanged (approximately 3x10(4) cells) with the exception of a doubling in the S/C IL-10(-/-) mice (approximately 6x10(4) cells, P<0.05). NO production (per million cells) was doubled in cells from S/C IL-10(-/-) (15.3 microM) mice compared with WT (7.6 microM, P<0.05). Inhibition of iNOS by L-N(5)-(1-iminoethyl)-ornithine reduced NO production in all S/C mice, confirming that the increase was a result of up-regulation of iNOS. We conclude that IL-10 is a critical cytokine regulating iNOS in murine airway cells and that its absence can lead to up-regulation of iNOS and development of allergic airway inflammation.


Subject(s)
Interleukin-10/physiology , Nitric Oxide/biosynthesis , Ornithine/analogs & derivatives , Respiratory System/metabolism , Aerosols , Animals , Biomarkers , Bronchoalveolar Lavage Fluid/cytology , Cell Count , Cells, Cultured , Enzyme Inhibitors/pharmacology , Eosinophilia/etiology , Eosinophilia/immunology , Immunization , Interleukin-10/deficiency , Interleukin-10/genetics , Lung/enzymology , Lung/immunology , Macrophages, Alveolar/physiology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type II , Nitrites/analysis , Ornithine/pharmacology , Ovalbumin/administration & dosage , Ovalbumin/immunology , RNA, Messenger/biosynthesis , Respiratory System/immunology , Specific Pathogen-Free Organisms
5.
Curr Opin Pharmacol ; 1(3): 230-4, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11712744

ABSTRACT

The field of cysteinyl leukotriene research has moved forward considerably in the past two years. Significant recent advances have been made in three areas: genetic control of the cysteinyl leukotriene response, in which alterations in both the promoter region and in transcribed mRNA have been described; the mechanisms by which cysteinyl leukotrienes promote the development of inflammation; and extensions in the clinical arena that support broader positioning of leukotriene modifiers in the therapy of asthma and allergic diseases.


Subject(s)
Anti-Asthmatic Agents/therapeutic use , Asthma/drug therapy , Leukotriene Antagonists/therapeutic use , Leukotrienes/genetics , Leukotrienes/physiology , Animals , Anti-Asthmatic Agents/pharmacology , Humans , Leukotriene Antagonists/pharmacology
6.
Am J Respir Crit Care Med ; 164(5): 759-63, 2001 Sep 01.
Article in English | MEDLINE | ID: mdl-11549529

ABSTRACT

The objective of this study was to determine whether initial maintenance therapy for the treatment of inflammation and bronchoconstriction associated with persistent asthma is more effective with a combination product (100 microg of fluticasone propionate and 50 microg of salmeterol [FSC]) administered twice daily through the Diskus device (GlaxoWellcome, Research Triangle Park, NC) or with montelukast at 10 mg once daily. A 12-wk, randomized, double-blind, double-dummy, multicenter study was conducted with 423 patients 15 yr of age and older with asthma and who were symptomatic while receiving short-acting beta(2)-agonists alone. At end point, FSC resulted in significantly greater increases in morning predose FEV(1) (0.54 +/- 0.03 vs. 0.27 +/- 0.03 L), morning peak expiratory flow (PEF) (89.9 +/- 6.7 vs. 34.2 +/- 4.7 L/min), evening PEF (69.9 +/- 5.8 vs. 31.1 +/- 4.5 L/min), the percentage of symptom-free days (48.9 +/- 2.9 vs. 21.7 +/- 2.5%), the percentage of rescue-free days (53.0 +/- 2.8 vs. 26.2 +/- 2.5%), and the percentage of nights with no awakenings (23.0 +/- 2.5 vs. 15.5+/-2.4%) compared with montelukast (p < or = 0.001, all comparisons). FSC significantly reduced asthma symptom scores (-1.0 +/- 0.1 vs. -0.6 +/- 0.1), rescue albuterol use (-3.3 +/- 0.2 vs. -1.9 +/- 0.2 puffs/d), and the number of exacerbations (0 vs. 11) compared with montelukast (p < 0.001). Both treatments were well tolerated. In summary, treatment of the two main components of asthma (inflammation and bronchoconstriction) with fluticasone propionate and salmeterol in a combination product was a more effective initial maintenance treatment strategy than treatment with montelukast, a single-mediator antagonist.


Subject(s)
Acetates/therapeutic use , Adrenergic beta-Agonists/therapeutic use , Albuterol/analogs & derivatives , Albuterol/therapeutic use , Androstadienes/therapeutic use , Anti-Asthmatic Agents/therapeutic use , Anti-Inflammatory Agents/therapeutic use , Asthma/drug therapy , Quinolines/therapeutic use , Adolescent , Adult , Aged , Cyclopropanes , Double-Blind Method , Drug Therapy, Combination , Female , Fluticasone , Humans , Male , Middle Aged , Salmeterol Xinafoate , Sulfides
7.
Am J Respir Crit Care Med ; 163(4): 881-6, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11282760

ABSTRACT

Inflammation is a critical component of asthma. Drugs that control asthma generally reduce the degree of airway inflammation. There is theoretical controversy surrounding the effects of beta(2)-agonists on airway inflammation, with some studies suggesting an anti-inflammatory effect, and others predicting a proinflammatory influence. We conducted a double-blind, placebo-controlled, crossover study of the effect of the long-acting beta(2)-agonist salmeterol on airway inflammation induced by segmental allergen challenge (SAC). We studied 13 allergic asthmatics controlled with as needed inhaled short-acting beta(2)-agonists alone, and used bronchoalveolar lavage 5 min and 48 h after SAC to assess airway inflammation, and the effects of salmeterol on this process. Salmeterol therapy improved FEV(1), but had no significant effect on the immediate or late cellular response to SAC. One measure of superoxide production was reduced, and interleukin-4 (IL-4) was reduced in baseline samples, but other indices of airway inflammation were unchanged by salmeterol therapy. We conclude that salmeterol therapy alone does not meaningfully reduce airway inflammation induced by SAC, but equally importantly, does not result in amplified inflammation.


Subject(s)
Adrenergic beta-Agonists/administration & dosage , Albuterol/analogs & derivatives , Albuterol/administration & dosage , Allergens , Asthma/drug therapy , Bronchial Hyperreactivity/diagnosis , Administration, Inhalation , Adult , Analysis of Variance , Asthma/complications , Asthma/diagnosis , Biomarkers/analysis , Bronchial Hyperreactivity/complications , Bronchial Provocation Tests , Bronchoalveolar Lavage Fluid/cytology , Bronchoscopy , Cross-Over Studies , Double-Blind Method , Female , Humans , Male , Pneumonia/complications , Pneumonia/drug therapy , Probability , Reference Values , Respiratory Function Tests , Salmeterol Xinafoate , Treatment Outcome
8.
Chest ; 116(6): 1638-45, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10593788

ABSTRACT

STUDY OBJECTIVE: This study aimed to establish whether the outpatient management of patients presenting with an asthma exacerbation to the emergency department (ED) was in compliance with the 1992 guidelines of the "International Consensus Report on the Diagnosis and Management of Asthma." DESIGN: Prospective, observational study using a researcher-administered questionnaire. SETTING: University tertiary referral ED. PATIENTS: Convenience sample of asthmatics (aged 18 to 54 years) presenting for asthma treatment between July 1, 1997, and June 30, 1998. RESULTS: Eighty-five asthmatic patients were enrolled. Of these, 34 patients (40%) smoked, 53 patients (62%) were undertreated with medication when compared to the consensus guidelines, and 74 patients (87%) had no written "plan of action." During an asthma attack, 9 patients (11%) did not use a bronchodilator as first-line action and 76 patients (89%) did not commence or increase the use of an inhaled steroid. Forty-nine patients (58%) did not know that bronchospasm occurred in asthma, and 53 patients (62%) did not know that bronchial swelling occurred. Twenty-six patients (31%) thought short-acting bronchodilator drugs were asthma preventers. Sixty-two patients (73%) could not adequately define peak expiratory flow (PF), 41 patients (48%) did not own a PF meter, and only 8 patients (9%) determined their PF daily. Fifty-three patients (62%) were reviewed by a physician once a year or less, and 18 patients (21%) noted family and friends as their only source of asthma education. CONCLUSIONS: The outpatient management of most asthma patients presenting to the ED did not comply with the consensus guidelines, and asthma knowledge was poor.


Subject(s)
Asthma/therapy , Emergency Service, Hospital/standards , Guideline Adherence , Practice Guidelines as Topic , Adolescent , Adult , Female , Health Knowledge, Attitudes, Practice , Hospitals, University , Humans , Male , Middle Aged , Patient Education as Topic , Pennsylvania , Prospective Studies , Severity of Illness Index
9.
Am J Respir Crit Care Med ; 160(4): 1157-64, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10508802

ABSTRACT

Respiratory syncytial virus (RSV) and adenovirus (Advs) serotype 3 (Adv3) and 7h (Adv7h) are associated with mild to severe respiratory infection and are indistinguishable during the acute phases of the illnesses. However, outcome and long-term prognosis are different with both infections. RSV infection is associated with later development of asthma, and Adv, mainly Adv7h, with severe lung damage, bronchiectasis, and hyperlucent lung. We hypothesized that this difference could be partly due to different immune responses induced by these viruses. To test this hypothesis we quantified TCD4+, TCD8+, and BCD19+ expressing the interleukin-2 receptor-alpha chain (CD25) and interferon-gamma (IFN-gamma), interleukin (IL)-10, and IL-4 in the supernatant of peripheral blood mononuclear cells (PBMC) from school children infected in vitro with and without RSV, Adv7h, and Adv3 and after phytohemagglutinin (PHA) stimulation in the presence or absence of these viruses at a multiplicity of infection (MOI) of 1. PBMC from every child produced more IL-10 (p

Subject(s)
Adenoviruses, Human/physiology , Cytokines/metabolism , Leukocytes, Mononuclear/metabolism , Respiratory Syncytial Virus, Human/physiology , Adenovirus Infections, Human/immunology , Cells, Cultured , Child , Humans , Interferon-gamma/metabolism , Interleukin-10/metabolism , Interleukin-4/metabolism , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/virology , Lymphocyte Activation , Lymphocyte Subsets/metabolism , Receptors, Interleukin-2/metabolism , Respiratory Syncytial Virus Infections/immunology
10.
Drugs Today (Barc) ; 35(8): 595-603, 1999 Aug.
Article in English | MEDLINE | ID: mdl-12973423

ABSTRACT

Asthma is a syndrome characterized by variable airflow limitation, airway hyperresponsiveness and airway inflammation. Considering asthma in aggregate, it is clear that a number of distinct mechanisms underlie the development of this disorder. In some patients, the mechanistic distinctions can be clearly drawn, and important therapeutic insights can be gained. In other patients, several mechanisms may coexist, or it may be impossible to separate them with current methods and technology. To distinguish subsets of asthma is more than an academic exercise. For both clinicians and asthma researchers, it is valuable to distinguish asthma subtypes as clearly as possible. Clinicians strive to prescribe the most effective, most safe, and most cost effective therapy possible, and understanding asthma subsets and their underlying mechanistic differences can substantively facilitate achieving that objective. Asthma research is often limited by significant, and sometimes dramatic intersubject variability. It is likely that at least some of that variability may arise from the (unrecognized) mechanistic heterogeneity of asthma. Better definition and selection of more homogeneous subsets of asthma may then lead to greater statistical power, and more definitive conclusions from asthma investigations.

11.
J Allergy Clin Immunol ; 102(6 Pt 1): 935-42, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9847434

ABSTRACT

BACKGROUND: Previous trials demonstrated the effectiveness of the leukotriene receptor antagonist zafirlukast in patients with mild-to-moderate asthma. OBJECTIVES: We sought to assess the efficacy and safety of zafirlukast and its effect on patients' quality of life (QOL) during a 13-week, double-blind, placebo-controlled, multicenter trial in adults and adolescents with moderate reversible airflow obstruction. METHODS: Patients (age range, 12 to 68 years) with total daytime asthma symptoms scores of 10 or greater over 7 consecutive days (maximum, 21/wk), FEV1 45% or greater but less than or equal to 80% of predicted value (>/=6 hours after beta2 -agonist), and reversible airway disease were randomized to 20 mg zafirlukast twice daily (nZ = 231) or placebo twice daily (nP = 223). Efficacy was assessed from changes in daytime and nocturnal symptoms, beta2 -agonist use, nasal congestion score, and pulmonary function. QOL was evaluated with a disease-specific Asthma Quality of Life Questionnaire. Safety was determined from adverse event information and clinical laboratory test results. RESULTS: Zafirlukast was significantly (P <.001) more effective than placebo, with reductions from baseline in the daytime asthma symptoms score (-23%), nighttime awakenings with asthma (-19%), and beta2 -agonist use (-24%) and improvements from baseline in morning (+25 L/min) and evening (+18 L/min) peak expiratory flow rates. Compared with placebo, zafirlukast significantly (P /=0.5-unit change from baseline; P

Subject(s)
Asthma/drug therapy , Bronchodilator Agents/therapeutic use , Lung Diseases, Obstructive/drug therapy , Tosyl Compounds/therapeutic use , Adolescent , Adult , Aged , Bronchodilator Agents/adverse effects , Child , Double-Blind Method , Female , Humans , Indoles , Male , Middle Aged , Phenylcarbamates , Quality of Life , Sulfonamides , Tosyl Compounds/adverse effects
12.
Am J Respir Crit Care Med ; 157(6 Pt 2): S238-45; discussion S245-8, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9647606

ABSTRACT

Zafirlukast is an orally active and selective cysteinyl leukotriene (cysLT) receptor antagonist. In humans, zafirlukast antagonized the effects of exogenously administered LTD4 and cysLTs released endogenously in response to physical and chemical stimuli. Zafirlukast antagonized LTD4-induced bronchoconstriction, with effects still evident 12 h after drug administration. In clinical models of asthma, zafirlukast inhibited bronchospasm after allergen or exercise challenge in patients with asthma. In multicenter trials in patients with chronic, stable asthma, zafirlukast reduced asthma symptoms, decreased as-needed beta-agonist use, and improved pulmonary function without increasing the number of adverse events. Zafirlukast also exhibited evidence of an anti-inflammatory effect in the lung in preliminary studies involving segmental antigen challenge. The results from these clinical trials demonstrate that zafirlukast is effective and safe for the prophylactic treatment of asthma.


Subject(s)
Anti-Asthmatic Agents/therapeutic use , Asthma/drug therapy , Bronchoconstriction/drug effects , Leukotriene Antagonists , Tosyl Compounds/therapeutic use , Anti-Asthmatic Agents/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Asthma/etiology , Asthma/metabolism , Asthma/physiopathology , Clinical Trials as Topic , Cross-Over Studies , Dose-Response Relationship, Drug , Double-Blind Method , Drug Interactions , Humans , Indoles , Multicenter Studies as Topic , Phenylcarbamates , Sulfonamides , Tosyl Compounds/pharmacology , Treatment Outcome
13.
Am J Respir Crit Care Med ; 157(5 Pt 1): 1381-9, 1998 May.
Article in English | MEDLINE | ID: mdl-9603112

ABSTRACT

The effect of zafirlukast (Z) to alter the inflammatory response to segmental antigen challenge (SAC) was assessed by bronchoalveolar lavage (BAL) in this double-blind, placebo-controlled, two-period, crossover trial in 11 allergic asthmatic patients. Patients with asthma and positive skin tests to antigen received 7 d of treatment with Z (20 mg twice daily) or placebo (P) during two trial periods 14 to 21 d apart. At steady state (Day 5), patients underwent SAC followed by BAL immediately after challenge and 48 h later. Purified alveolar macrophages were analyzed ex vivo for phorbol myristate acetate (PMA)-driven superoxide release. Results were analyzed by analysis of variance (ANOVA). Forty-eight hours after SAC, Z therapy was associated with significantly reduced BAL lymphocytes and alcian blue-positive cells (presumably basophils) compared with P (p < 0.01), with a trend toward reduced numbers of alveolar macrophages (p = 0.06). PMA-driven superoxide release by purified alveolar macrophages was significantly reduced 48 h after SAC in the Z versus P arms (p < 0.05). Reduction of basophil influx, mediator release, and cellular activation may be important in attenuating the late phase of asthma. Collectively, the data suggest that zafirlukast therapy alters cellular infiltration and activation associated with antigen challenge.


Subject(s)
Antigens/administration & dosage , Asthma/metabolism , Bronchoalveolar Lavage Fluid/chemistry , Inflammation Mediators/metabolism , Leukotriene Antagonists , Ribonucleases , Tosyl Compounds/therapeutic use , Adolescent , Adult , Antigens/immunology , Asthma/drug therapy , Asthma/pathology , Bronchoalveolar Lavage Fluid/cytology , Cell Count/drug effects , Cross-Over Studies , Double-Blind Method , Eosinophil-Derived Neurotoxin , Eosinophils , Female , Histamine Release/drug effects , Humans , Indoles , Leukotrienes/analysis , Macrophages, Alveolar/metabolism , Macrophages, Alveolar/pathology , Male , Middle Aged , Neurotoxins/analysis , Phenylcarbamates , Sulfonamides , Superoxides/metabolism , Tumor Necrosis Factor-alpha/analysis
14.
Am J Respir Crit Care Med ; 157(3 Pt 1): 692-7, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9517577

ABSTRACT

The incorporation of bronchoscopy and bronchoscopic procedures into the investigation of asthma mechanisms, treatment, and in particular, the role of airway inflammation has contributed significantly to the enhanced understanding of this disease. Carefully drafted guidelines have allowed the gradual inclusion of subjects with more severe disease in studies utilizing bronchoscopic investigative tools. Many more questions remained unanswered, including the importance of persistence of airway inflammation in asymptomatic asthma, the specific antiinflammatory effects of new (and old) asthma therapies, the contribution of airway structural changes (subepithelial fibrosis) to nonreversible obstruction, the role of antiinflammatory versus proinflammatory cytokines in the pathogenesis of airway inflammation and the heterogeneity of disease expression in various groups of subjects. We are confident that current and future meticulously designed and executed research studies utilizing bronchoscopic techniques will significantly add to our knowledge of disease mechanisms and lead us to new and improved treatments for asthma.


Subject(s)
Asthma/diagnosis , Bronchoscopy , Airway Obstruction/pathology , Allergens , Anti-Inflammatory Agents/therapeutic use , Antigens , Asthma/drug therapy , Asthma/immunology , Asthma/pathology , Asthma/physiopathology , Biopsy , Bronchi/pathology , Bronchial Provocation Tests/methods , Bronchoalveolar Lavage/methods , Bronchoalveolar Lavage Fluid/cytology , Bronchoscopy/methods , Cytodiagnosis , Cytokines/physiology , Humans , Pulmonary Fibrosis/pathology , Safety
15.
Am J Respir Crit Care Med ; 156(1): 190-5, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9230746

ABSTRACT

Viral infections have been associated with cellular immune responses and production of Th-1 cytokines. Respiratory syncytial virus (RSV), however, induces virus-specific IgE, which might be a consequence of a Th-2-like activation. To test this hypothesis we quantified interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) in the supernatant of peripheral blood mononuclear cells cultured for 24 and 48 h in the presence or absence of phytohemaglutinin and pokeweed mitogen and the lymphocyte phenotypes to analyze subsets and their activation markers, from 15 hospitalized infants during an acute lower respiratory infection caused by RSV and 17 healthy control infants from 1 to 15 mo of age. Compared with the control infants, those infected with RSV had an increase in the number of B-cells (p < 0.02) and decreases in both CD8+ T-cells (p < 0.01) and activated CD8+/CD25+ suppressor/ cytotoxic T-cells (p < 0.007). In RSV-infected infants, IFN-gamma production was subtotally suppressed, whereas IL-4 production was decreased to a lesser degree, giving significantly (p < 0.001) increased IL-4/IFN-gamma ratio compared with that in the control infants. These findings suggest a predominant Th-z-like response in RSV-infected infants, which could explain some aspects of the immunopathogenesis of RSV infection and the RSV-specific and nonspecific IgE antibody responses observed.


Subject(s)
Interferon-gamma/blood , Interleukin-4/blood , Respiratory Syncytial Virus Infections/immunology , Antigens, Viral/blood , Case-Control Studies , Cells, Cultured , Humans , Infant , Leukocytes, Mononuclear/immunology , Lymphocyte Activation , Lymphocyte Subsets/immunology , Respiratory Syncytial Viruses/immunology
16.
Am J Respir Crit Care Med ; 155(5): 1515-21, 1997 May.
Article in English | MEDLINE | ID: mdl-9154851

ABSTRACT

The response to antigen is an important factor in the development of airway inflammation. Segmental bronchoprovocation (SBP) with antigen and subsequent bronchoalveolar lavage (BAL) have provided valuable insight into the mechanisms of allergic inflammation. To determine the features of allergic airway response in asthma, 19 subjects with mild asthma underwent antigen SBP in a dose-dependent manner. The amount of antigen used in SBP was 0 (saline), and 1, 5, or 20% of the antigen dose required to drop the FEV1 by 20% (APD20). BAL was done at 5 min and 48 h after SBP. BAL histamine levels increased modestly 5 min after antigen SBP. At 48 h, there was a marked increase in eosinophils and IL-5 concentration even in airway segments where the release of histamine was small. Moreover, eosinophils correlated with IL-5 levels at 48 h (r = 0.63; p < 0.001), but not with BAL histamine concentrations at 5 min. GM-CSF levels did not increase after antigen SBP and did not correlate with eosinophils. These observations indicate that asthmatic subjects can develop a dose-dependent response to antigen SBP that is characterized by a modest increase in histamine immediately after antigen exposure, and marked eosinophilia, which appears proportionately greater than the histamine response and relatively greater than what is seen in allergic nonasthmatic subjects. This feature might be important to the eventual development of airway inflammation in asthma.


Subject(s)
Allergens/administration & dosage , Asthma/immunology , Bronchial Provocation Tests , Adult , Allergens/immunology , Animals , Asthma/pathology , Asthma/physiopathology , Bronchoalveolar Lavage Fluid/chemistry , Bronchoalveolar Lavage Fluid/cytology , Bronchoscopy , Cats , Cell Count , Dose-Response Relationship, Immunologic , Eosinophils , Female , Forced Expiratory Volume , Granulocyte-Macrophage Colony-Stimulating Factor/analysis , Histamine/analysis , Humans , Interleukin-5/analysis , Male , Middle Aged , Poaceae , Pollen , Spirometry , Time Factors
17.
J Allergy Clin Immunol ; 98(5 Pt 2): S46-50; discussion S64-6, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8939176

ABSTRACT

In many patients with asthma, exposure to allergen results in worsening symptoms, pulmonary dysfunction, and increased airway inflammation. In this study, segmental allergen challenge and bronchoalveolar lavage were used to evaluate the airway responses at 5 minutes and 48 hours and to study the extent of inhibition of the response by pretreatment with nedocromil sodium in eight subjects with allergic asthma in a double-blind, placebo-controlled trial. At 5 minutes after challenge, nedocromil sodium pretreatment significantly reduced histamine concentrations, with a trend toward a concomitant reduction in tryptase levels. Nedocromil sodium did not affect the increase in total protein, total cell counts, or cell concentrations that occurred 48 hours after challenge, but it did significantly reduce eosinophil recruitment. Eosinophil activation, assessed as release of granule proteins, was unaffected. A significant positive correlation was shown between the degree of histamine reduction at 5 minutes and the degree of reduction of eosinophil influx at 48 hours, raising the possibility that eosinophil influx into the airway may depend on mediators or cytokines released during the immediate response to allergen.


Subject(s)
Asthma/drug therapy , Bronchial Hyperreactivity/immunology , Nedocromil/therapeutic use , Aerosols , Anti-Asthmatic Agents/therapeutic use , Antigens/pharmacology , Bronchoalveolar Lavage Fluid/chemistry , Chymases , Double-Blind Method , Histamine Release , Humans , Inflammation Mediators/metabolism , Male , Serine Endopeptidases/metabolism , Tryptases
18.
Am J Respir Crit Care Med ; 153(2): 633-7, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8564110

ABSTRACT

The inflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha) and interleukin-1-beta (IL-1 beta), have been associated with accelerated metabolism and protein turnover following exogenous administration in normal humans. We hypothesized that these inflammatory cytokines might contribute to the weight-losing process in patients with chronic obstructive pulmonary disease (COPD). COPD patients were identified prospectively as "weight losers" (WL; n = 10) if they reported > 5% weight loss during the preceding year or as "weight stable" (WS; n = 10) if their body weight fluctuated < or = 5%. Age-matched healthy volunteers were selected as the control group (C; n = 13). Monocytes were isolated from a peripheral blood sample, cultured, and exposed to lipopolysaccharide (LPS). The concentration of TNF-alpha and IL-1 beta in the monocyte supernatant was measured using a four layer enhanced ELISA. No significant difference in LPS-stimulated IL-1 beta production was found in the three study populations. However, LPS-stimulated TNF-alpha production (mean [range] ng/ml) by monocytes was significantly higher in the WL COPD patients (20.2 [6.3 to 44.8]), compared with WS patients (6.9 [1.5 to 16.6]), and C subjects (5.7 [0 to 61.8]). This difference was not maintained at 6 mo follow-up in the absence of ongoing weight loss. Definition of a causal relationship between TNF-alpha production and weight loss will require further understanding of the relationship between energy metabolism and TNF-alpha production in these patients.


Subject(s)
Lung Diseases, Obstructive/blood , Monocytes/metabolism , Tumor Necrosis Factor-alpha/biosynthesis , Weight Loss , Aged , Cells, Cultured , Energy Metabolism , Female , Forced Expiratory Volume , Humans , Interleukin-1/metabolism , Lipopolysaccharides/pharmacology , Lung Diseases, Obstructive/physiopathology , Male , Middle Aged , Vital Capacity
19.
J Allergy Clin Immunol ; 96(3): 375-85, 1995 Sep.
Article in English | MEDLINE | ID: mdl-7560640

ABSTRACT

Eosinophils are hypothesized to be crucial in the development of allergic airway inflammation; however, the actual mechanisms that determine their inflammatory activity are still largely undefined. To investigate the factors that regulate eosinophil function in allergic airway disease, we have previously used segmental bronchoprovocation with allergen to study ex vivo eosinophil function. To determine whether the functional changes associated with airway eosinophils obtained by bronchoalveolar lavage 48 hours after antigen challenge are caused by exposure to airway-generated cytokines, normodense blood eosinophils were cultured in vitro with recombinant human interleukin-5 (IL-5) or granulocyte-macrophage colony stimulating factor (GM-CSF). The effect of cytokine exposure was then evaluated on selected cell functions. In vitro incubation with these cytokines for 24 hours significantly increased eosinophil membrane expression of CD18 and CD11b compared with culture in medium alone or eosinophils obtained by bronchoalveolar lavage. N-formyl-methionyl-leucyl-phenylalanine-stimulated superoxide anion generation was slightly but significantly enhanced by incubation with IL-5 but not with GM-CSF. In addition, spontaneous adhesion to human umbilical vein endothelial cell monolayers was increased after exposure to both IL-5 and GM-CSF. However, activated adhesion was enhanced only by culture with IL-5 and stimulation with N-formyl-methionyl-leucyl-phenylalanine. The magnitude of functional changes after in vitro preincubation of eosinophils with these cytokines did not achieve levels of superoxide anion and adhesion noted with airway eosinophils obtained after segmental bronchoprovocation with allergen. These observations raise the possibility that the contribution of IL-5 and GM-CSF to phenotypic changes of airway eosinophils is principally to enhance survival and expression of adhesion proteins. These data also suggest that, in addition to the generation of proinflammatory cytokines, other factors contribute to phenotypic changes in eosinophils as they migrate from the blood to the airway.


Subject(s)
Eosinophils/drug effects , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Interleukin-5/pharmacology , Blood Cells/drug effects , Blood Cells/physiology , Bronchoalveolar Lavage Fluid/cytology , Cell Adhesion/drug effects , Cell Survival/drug effects , Cells, Cultured , Cytokines/pharmacology , Eosinophils/physiology , Humans , Integrins/metabolism , Rhinitis, Allergic, Perennial/pathology , Rhinitis, Allergic, Seasonal/pathology , Superoxides/metabolism
20.
J Clin Invest ; 94(6): 2200-8, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7989575

ABSTRACT

Many patients with asthma have increased wheezing with colds. We hypothesized that rhinovirus colds might increase asthma by augmenting airway allergic responses (histamine release and eosinophil influx) after antigen challenge. Seven allergic rhinitis patients and five normal volunteers were infected with rhinovirus type 16 (RV16) and evaluated by segmental bronchoprovocation and bronchoalveolar lavage. Segmental challenge with saline and antigen was performed 1 mo before infection, during the acute infection, and 1 mo after infection. Lavage was performed immediately and 48 h after antigen challenge. Data were analyzed by two-way analysis of variance, and a P value of < or = 0.05 was considered to be significant. All volunteers inoculated with RV16 developed an acute respiratory infection. BAL fluid obtained from allergic rhinitis subjects during the acute viral infection, and 1 mo after infection, showed the following significant RV16-associated changes after antigen challenge: (a) an enhanced release of histamine immediately after local antigen challenge; (b) persistent histamine leak 48 h afterwards; and (c) a greater recruitment of eosinophils to the airway 48 h after challenge. These changes were not seen in non-allergic volunteers infected with RV16 and challenged with antigen, nor in allergic volunteers repetitively challenged with antigen but not infected with RV16, nor in RV16 infected allergic volunteers sham challenged with saline. We conclude that rhinovirus upper respiratory infection significantly augments immediate and late allergic responses in the airways of allergic individuals after local antigen challenge. These data suggest that one mechanism of increased asthma during a cold is an accentuation of allergic responses in the airway which may then contribute to bronchial inflammation.


Subject(s)
Bronchi/immunology , Common Cold/immunology , Hypersensitivity/immunology , Rhinitis, Allergic, Seasonal/immunology , Rhinovirus/immunology , Bronchoalveolar Lavage Fluid/cytology , Bronchoscopy , Common Cold/complications , Eosinophils/cytology , Histamine/analysis , Humans , Hypersensitivity/etiology , Inflammation/etiology , Inflammation/immunology , Peptide Hydrolases/analysis , Plant Proteins/immunology , Pollen/immunology , Rhinitis, Allergic, Seasonal/etiology , Time Factors , Tumor Necrosis Factor-alpha/analysis
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