Intravenous immunoglobulin (IVIG) therapy is used in inflammatory diseases but the use of immunog... more Intravenous immunoglobulin (IVIG) therapy is used in inflammatory diseases but the use of immunoglobulin as a treatment for acute lung injury (ALI) has not been previously studied. Transforming growth factor beta (TGF-β) plays a critical role in the pathogenesis of of ALI. Therefore we examined the levels of TGF-β and lung inflammation scores in IVIG treated ALI models. Methods: Intratracheal lipopolysacccharide was given to rats. Groups 1 and 3 received saline, whereas group 2 received IVIG. 24 h later saline was given to groups 1 and 2 and IVIG to group 3. Blood samples and bronchoalveolar lavage (BAL) fluids were obtained from each group and sacrificed for pathological evaluation. Results: BAL TGF-β levels of groups 2 and 3 on day 30, were lower compared to their levels of day 2 (p = 0.01, p = 0.01). BAL TGF-β levels of groups 2 and 3 were lower than the levels of group 1 on day 30 (p = 0.002, p = 0.001). Pathological examination revealed that the inflammation scores of groups 2 and 3 on day 30, were lower than the scores of day 2 (p = 0.02, p = 0.01). Inflammation scores of group 2 were lower than group 1 on day 30 (p = 0.02). Moderate fibrosis was seen in half of the rats from group 1 and one rat from group 2. Conclusion: High-dose IVIG decreased lung inflammation scores and BAL TGF-β1 levels and this therapy would give even better results if it is given earlier.
Communications for this section will be published as space and priorities permit. The comments sh... more Communications for this section will be published as space and priorities permit. The comments should not exceed 350 words in length, with a maximum of five references; one figure or table can be printed. Exceptions may occur under particular circumstances. Contributions may include comments on articles published in this periodical, or they may be reports of unique educational character. Please include a cover letter with a complete list of authors (including full first and last names and highest degree), corresponding author's address, phone number, fax number, and email address (if applicable). An electronic version of the communication should be included on a 3.5-inch diskette. Specific permission to publish should be cited in the cover letter or appended as a postscript. CHEST reserves the right to edit letters for length and clarity.
Background: Bronchodilator therapy is central to the symptomatic management of chronic obstructiv... more Background: Bronchodilator therapy is central to the symptomatic management of chronic obstructive pulmonary disease (COPD), and treatment with short-acting bronchodilators is recommended in patients with mild COPD. Objective: This study aimed to evaluate the onset of effect of single-dose formoterol 9 mg versus single-dose salmeterol 50 mg in patients with moderate COPD. Methods: In this multicentre, double-blind, double-dummy, placebo-controlled, three-way single-dose crossover study, patients ‡40 years of age with moderate COPD were randomized to single-dose formoterol 9 mg via Turbuhaler Ò plus placebo via Diskus Ò , single-dose salmeterol 50 mg via Diskus Ò plus placebo via Turbuhaler Ò or placebo via Turbuhaler Ò and Diskus Ò (washout period 2-7 days). Terbutaline 0.5 mg/actuation via Turbuhaler Ò was used as reliever medication throughout. The primary endpoint was forced expiratory volume in 1 second (FEV 1) at 5 minutes post-dose. Secondary endpoints included proportion of patients achieving ‡12% increase in FEV 1 at 5 minutes post-dose.
A 49-year-old woman underwent a pneumonectomy because of a mass in the middle lobe. Histological ... more A 49-year-old woman underwent a pneumonectomy because of a mass in the middle lobe. Histological examination of the tumour showed a well-differentiated fetal adenocarcinoma (WDFA). This rare tumour appears to be associated with an excellent prognosis in the absence of metastases following surgical resection.
An otherwise healthy 44-yr-old man experienced a serious attack of bronchial obstruction after wo... more An otherwise healthy 44-yr-old man experienced a serious attack of bronchial obstruction after working with resins and hardeners, releasing fumes of a mixture of an alipathic and a cycloaliphatic diamine hardener. Eight hours after deliberate challenge with the hardener a large increase of airway resistance was found. Seventy-two hours after challenge, eosinophilia in the bronchoalveolar lavage (BAL) fluid together with a decrease of peripheral eosinophils was seen. After cessation of contact with this hardener, no more acute episodes occurred, although maintenance treatment with a topical corticosteroid and a beta 2-agonist remained necessary. A BAL performed 1 yr later showed a normal cell distribution. The results suggest that these aliphatic and cycloaliphatic diamine hardeners may be occupational hazards. Eosinophil inflammation may play a causal role.
Bronchial hyperresponsiveness (BHR) to methacholine and adenosine 5'-monophosphat... more Bronchial hyperresponsiveness (BHR) to methacholine and adenosine 5'-monophosphate (AMP) was studied in 15 allergic asthmatic patients before and 3 and 24 h after allergen challenge with house dust mite (HDM). Subjects attended the clinic on 3 consecutive days. On the first day a control solution was inhaled, and methacholine or AMP challenge was performed 3 h later. The next day HDM was inhaled, and 3 and 24 h later methacholine or AMP challenge was performed again. There were no significant difference in FEV1 baseline value between any of the study days. PD20 HDM, percentage decrease in FEV1, and AUC for both the EAR and LAR were not significantly different in the methacholine and AMP studies. After HDM challenge, PC20 methacholine decreased significantly from a geometric mean (+/- SEM) starting value of 1.39 +/- 0.63 mg/ml to 0.30 +/- 0.78 mg/ml (p less than 0.001) at 3 h and to 0.22 +/- 0.75 mg/ml (p less than 0.001) at 24 h. The magnitude of the decrease in PC20 methacholine at 3 h correlated with the severity of the late asthmatic reaction (LAR) as measured by the percentage fall in FEV1 and area under the curve (AUC) (r = -0.60 and r = 0.55; p less than 0.05). A significant decrease was observed in the PC20 AMP at 3 h, from a geometric mean value of 12.2 +/- 0.96 mg/ml after challenge with the control solution to 4.47 +/- 0.99 mg/ml (p less than 0.05) after HDM challenge.(ABSTRACT TRUNCATED AT 250 WORDS)
Severe asthma is characterized by persistent T-ceil activation, as demonstrated in both periphera... more Severe asthma is characterized by persistent T-ceil activation, as demonstrated in both peripheral blood and bronchial mucosa. Endobronchial biopsy specimens of patients with severe, corticosteroid-dependent asthma revealed increased expression of CD25+ on mucosal T cells. Increased immunoreactivity for IL-5 further supports the evidence that the inflammatory response is orchestrated by THSype T cells. Peripheral blood eosinophils and total serum IgE levels were increased in the absence of allergen and despite optimal treatment. The chemokine 1L-8 may also be an aggravating factor in severe asthma; as well as being a potent chemotaetic and activating factor for neutrophiIs, it may also be chemoattractant for eosinophils. We have recently detected increased levels of free IL-8 in the peripheral blood of patients with chlvnic severe asthma but not in healthy control subjects or in patients with mild asthma, even after allergen challenge. In patients with severe asthma there may be an imbalance between IL-8 production and the blocking capacity of IL-8 autoantibodies. Higher levels of IL-8 complexed to lgA autoantibody and increased numbers of activated T cells were also found in patients with unstable asthma compared with patients who had severe but stable disease. We conclude that IL-8 may provide an additional marker of asthma severity and corticosteroid responsiveness.
Bronchial hyperresponsiveness (BHR) to methacholine was studied in 14 patients with asthma andJiv... more Bronchial hyperresponsiveness (BHR) to methacholine was studied in 14 patients with asthma andJive healthy control subjects, with and without pretreatment with nedocromil sodium, 3 and 24 hours after allergen challenge. Eleven patients demonstrated a dual asthmatic response. A significant decrease in the provocative concentration causing a 20% fall in FEV, was found ffom a geometric mean starting value of I .I8 mglml on the control day to 0.24 mglml (p < 0.001) and to 0.17 mglml (p < 0.001) 3 and 24 hours afer allergen challenge. A significant correlation was observed between the increased BHR at 3 hours and the magnitude of the late response (r =-0.57; p < 0.05). Nedocromil sodium (6 mg) significantly inhibited the increase in BHR, 1 mglml (p < 0.001) at 3 hours and 0.50 mglml (p < 0.001) at 24 hours. Nedocromil sodium shifted the severity of the early allergic reaction (EAR) from mean-34.8% to-6.9% and inhibited the later allergic reaction (EAR) from-30.5% to + 0.4% (p < 0.005). From the study can be concluded that nedocromil sodium inhibits the EAR and LAR and the allergen-induced increase in BHR. The inhibitory effect of nedocromil sodium on the EAR may be related to its ability to inhibit the increased BHR before the development of the LAR. (JALLERGYCLINIMMINOL 1991;87:993-1001.) BHR, a characteristic feature of asthma, is related to the severity of the disease and the need for therapy. '3 * The precise link between symptoms, BHR, and airway inflammation is still uncertain.3, 4 BHR can be assessed by direct and indirect stimuli. It is supposed that the bronchoconstriction induced by methacholine results from direct stimulation of the smooth muscle itself.5 BHR increases in sensitized patients during natural exposure to airborne allergens or occupational allergens that induce asthma. Conversely, removal from environmental exposure to domestic or occupational allergens often results in a decreased BHR.6-9
To examine the role of the bronchial microvasculature and adhesion molecule expression in severe ... more To examine the role of the bronchial microvasculature and adhesion molecule expression in severe asthma, the authors have performed an immunohistochemical study on bronchial biopsies comparing 15 glucocorticoid-dependent asthmatics, 15 mild asthmatics and eight control subjects. Serially cut glycol methacrylate-embedded sections were stained with monoclonal antibodies identifying the vessel marker EN-4, intercellular adhesion molecule (I-CAM)-1, vascular cell adhesion molecule (VCAM)-1, E-and P-selectin. Sections were also stained for lymphocyte function associated antigen (LFA)-1 and very late antigen (VLA)-4. By comparison with mild asthma and nonasthma, severe asthma was characterized by increased numbers of submucosal vessels (p=0.009) which was associated with increased numbers of vessels expressing ICAM-1 (p=0.005). A highly significant correlation was found between the total number of EN-4+ vessels and the vessels expressing ICAM-1 (r=0.85, p=0.01). In contrast, E-selectin expression was lower in severe as compared with mild asthma (p=0.01) but not different from normal. No differences were found between the three groups in the expression of VCAM-1 and Pselectin nor in numbers of LFA-1+ and VLA-4+ cells. The results of this study support the notion that mucosal neovascularization is an important feature of airways remodelling in severe asthma. This is associated with a relatively higher density of vessels expressing intercellular adhesion molecule-1, although the expression of this adhesion molecule per vessel was not raised.
To improve our understanding of the inflammatory mechanisms undererlying severe disease, a biopsy... more To improve our understanding of the inflammatory mechanisms undererlying severe disease, a biopsy study was performed comparing 15 clinically unstable glucocorticoid-dependent asthmatics, 10 mild asthmatics, and 10 control subjects. Compared with mild asthma, severe asthma was characterized by reduced mucosal eosinophilia. Whilst no significant differences were found in the numbers of mast cells, neutrophils, CD3+ and CD4+ T-cells between the three groups, up to a 4-fold increase in the numbers of activated T-lymphocytes bearing the interleukin (IL)-2 receptor (IL-2R) was found in the mucosa in severe asthma compared to mild asthma (p=0.03) and control subjects (p=0.003). Compared to control subjects, the mucosa of severe asthmatics contained significantly (p=0.02) higher numbers of IL-5+ cells, with no differences between mild and severe disease. In contrast, staining for the anti-IL-4 monoclonal antibody 3H4 revealed that biopsies from mild asthmatics contained more IL-4+ cells than biopsies from severe asthmatics and control subjects (p=0.0008). In the severe asthmatics, a close correlation (r s =0.76, p=0.005) was found between the numbers of IL-2R-bearing cells and the variability in peak expiratory flow. In conclusion, persistent T-cell activation is a prominent feature of severe asthma. These results also indicate that interleukin-5, and not interleukin-4, is upregulated in severe disease.
The extent of epithelial injury in asthma is reflected by expression of the epidermal growth fact... more The extent of epithelial injury in asthma is reflected by expression of the epidermal growth factor receptor (EGFR), which is increased in proportion to disease severity and is corticosteroid refractory. Although the EGFR is involved in epithelial growth and differentiation, it is unknown whether it also contributes to the inflammatory response in asthma. Because severe asthma is characterized by neutrophilic inflammation, we investigated the relationship between EGFR activation and production of IL-8 and macrophage inhibitory protein-1 alpha (MIP-1alpha) using in vitro culture models and examined the association between epithelial expression of IL-8 and EGFR in bronchial biopsies from asthmatic subjects. H292 or primary bronchial epithelial cells were exposed to EGF or H2O2 to achieve ligand-dependent and ligand-independent EGFR activation; IL-8 mRNA was measured by real-time PCR and IL-8 and MIP-1alpha protein measured by enzyme-linked immunosorbent assay (ELISA). Epithelial IL-8 and EGFR expression in bronchial biopsies from asthmatic subjects was examined by immunohistochemistry and quantified by image analysis. Using H292 cells, EGF and H2O2 increased IL-8 gene expression and release and this was completely suppressed by the EGFR-selective tyrosine kinase inhibitor, AG1478, but only partially by dexamethasone. MIP-1alpha release was not stimulated by EGF, whereas H2O2 caused a 1.8-fold increase and this was insensitive to AG1478. EGF also significantly stimulated IL-8 release from asthmatic or normal primary epithelial cell cultures established from bronchial brushings. In bronchial biopsies, epithelial IL-8, MIP-1alpha, EGFR and submucosal neutrophils were all significantly increased in severe compared to mild disease and there was a strong correlation between EGFR and IL-8 expression (r = 0.70, P &lt; 0.001). These results suggest that in severe asthma, epithelial damage has the potential to contribute to neutrophilic inflammation through enhanced production of IL-8 via EGFR- dependent mechanisms.
American Journal of Respiratory and Critical Care Medicine, 1997
We have tested the hypothesis that the expression of interleukin-8 (IL-8) is increased in bronchi... more We have tested the hypothesis that the expression of interleukin-8 (IL-8) is increased in bronchial tissue and circulating leukocytes of atopic asthmatics, indicating a role for this chemokine in asthma. The concentration of IL-8 in its free form and complexed with IgG or IgA was measured by ELISA in bronchial tissue, serum, and lysates of freshly isolated peripheral blood mononuclear cells and granulocytes from subjects with mild or severe asthma and nonatopic nonasthmatic subjects. Serum ECP was measured by fluorescent enzyme immunoassay. Free IL-8 was detected in the sera (n = 44) and bronchial tissue (n = 9) of all subjects with severe atopic asthma, but it was undetectable in normal subjects and subjects with mild atopic asthma, suggesting that free IL-8 is a marker of severe asthma. A positive correlation between free IL-8 and serum ECP levels found in severe disease suggests that IL-8 is associated with eosinophil activation. Complexes of IL-8 with IgA and IgG were detected in all serum and tissue samples. However, the levels of the IL-8-IgA complex were increased in the bronchial mucosa in asthma, and in blood were related to disease activity. Together, these results point to upregulation of IL-8 production in asthma and the induction of IL-8 binding immunoglobulins of the IgA class in the inflamed mucosa. We suggest a proinflammatory role for these complexes in lung tissue.
American Journal of Respiratory and Critical Care Medicine, 1994
The long-acting beta 2-agonist salmeterol has been suggested to have other pharmacologic activiti... more The long-acting beta 2-agonist salmeterol has been suggested to have other pharmacologic activities, that is, antiinflammatory capacities, in addition to its bronchodilator properties. We investigated the protective effect of 50 micrograms salmeterol in a placebo-controlled study on house dust mite-induced early- and late-phase reactions in 19 atopic asthmatic subjects. FEV1 and methacholine airway reactivity (AR) were measured. Eosinophils and their activation markers in peripheral blood were counted as indirect parameters of inflammation. Corrections were made for confounding of bronchodilator effects by salmeterol and the spontaneous diurnal variation, using saline inhalation as a control. Salmeterol completely inhibited the fall in FEV1 up to 10 h after the house dust mite challenge. Nevertheless, after correction, a biphasic response was present in the salmeterol group. Salmeterol protected against the allergen-associated increase in AR 3 h after the challenge, but no protection was observed after 24 h. Salmeterol did not inhibit the allergen-induced changes in total number of eosinophils and their activation markers in peripheral blood. These data suggest that a single dose of salmeterol modifies allergen-induced airway responses, above all by sustained bronchodilation.
The phenotypic cellular profile of bronchial lavage (BL) and bronchoalveolar lavage (BAL) was stu... more The phenotypic cellular profile of bronchial lavage (BL) and bronchoalveolar lavage (BAL) was studied in 7 single early (SR) and 10 dual asthmatic responders (DR). Lavage was performed, after previously having determined bronchial hyperresponsiveness to histamine and the response to house dust mite (HDM) challenge. The recovered lavage fluid was separated in two fractions, BL and BAL. Total fluid recovery and cell number from the BL and BAL were comparable in both patient groups. Differential cell counting and immunocytochemistry were performed. DR had a significantly higher number of eosinophils and EG2+ cells in BL but not in their BAL. No differences could be found in CD4+, CD8+, and HLA-DR+ cells. A strong correlation was found between eosinophils in the BL+ and EG2+ cells in the BL (r = 0.79, p &lt; 0.001) and between eosinophils in the BL and peripheral blood eosinophils (r = 0.70, p &lt; 0.0025). The number of EG2+ cells and the number of epithelial cells in both BL and BAL showed a correlation (r = 0.55, p &lt; 0.05). Dual responders had a higher total IgE (p &lt; 0.01), and total serum IgE correlated well with the eosinophils in the BL (r = 0.85, p &lt; 0.0001). Our observations demonstrate cellular differences in the lung on mainly a bronchial level between single early and dual asthmatic responders. A bronchial lavage eosinophil and EG2+ cell count and higher blood total IgE level are associated with the tendency to develop a dual asthmatic response.
Low-dose methotrexate treatment in severe glucocorticoid-dependent asthma: effect on mucosal infl... more Low-dose methotrexate treatment in severe glucocorticoid-dependent asthma: effect on mucosal inflammation and in vitro sensitivity to glucocorticoids of mitogen-induced T-cell proliferation.
Intravenous immunoglobulin (IVIG) therapy is used in inflammatory diseases but the use of immunog... more Intravenous immunoglobulin (IVIG) therapy is used in inflammatory diseases but the use of immunoglobulin as a treatment for acute lung injury (ALI) has not been previously studied. Transforming growth factor beta (TGF-β) plays a critical role in the pathogenesis of of ALI. Therefore we examined the levels of TGF-β and lung inflammation scores in IVIG treated ALI models. Methods: Intratracheal lipopolysacccharide was given to rats. Groups 1 and 3 received saline, whereas group 2 received IVIG. 24 h later saline was given to groups 1 and 2 and IVIG to group 3. Blood samples and bronchoalveolar lavage (BAL) fluids were obtained from each group and sacrificed for pathological evaluation. Results: BAL TGF-β levels of groups 2 and 3 on day 30, were lower compared to their levels of day 2 (p = 0.01, p = 0.01). BAL TGF-β levels of groups 2 and 3 were lower than the levels of group 1 on day 30 (p = 0.002, p = 0.001). Pathological examination revealed that the inflammation scores of groups 2 and 3 on day 30, were lower than the scores of day 2 (p = 0.02, p = 0.01). Inflammation scores of group 2 were lower than group 1 on day 30 (p = 0.02). Moderate fibrosis was seen in half of the rats from group 1 and one rat from group 2. Conclusion: High-dose IVIG decreased lung inflammation scores and BAL TGF-β1 levels and this therapy would give even better results if it is given earlier.
Communications for this section will be published as space and priorities permit. The comments sh... more Communications for this section will be published as space and priorities permit. The comments should not exceed 350 words in length, with a maximum of five references; one figure or table can be printed. Exceptions may occur under particular circumstances. Contributions may include comments on articles published in this periodical, or they may be reports of unique educational character. Please include a cover letter with a complete list of authors (including full first and last names and highest degree), corresponding author's address, phone number, fax number, and email address (if applicable). An electronic version of the communication should be included on a 3.5-inch diskette. Specific permission to publish should be cited in the cover letter or appended as a postscript. CHEST reserves the right to edit letters for length and clarity.
Background: Bronchodilator therapy is central to the symptomatic management of chronic obstructiv... more Background: Bronchodilator therapy is central to the symptomatic management of chronic obstructive pulmonary disease (COPD), and treatment with short-acting bronchodilators is recommended in patients with mild COPD. Objective: This study aimed to evaluate the onset of effect of single-dose formoterol 9 mg versus single-dose salmeterol 50 mg in patients with moderate COPD. Methods: In this multicentre, double-blind, double-dummy, placebo-controlled, three-way single-dose crossover study, patients ‡40 years of age with moderate COPD were randomized to single-dose formoterol 9 mg via Turbuhaler Ò plus placebo via Diskus Ò , single-dose salmeterol 50 mg via Diskus Ò plus placebo via Turbuhaler Ò or placebo via Turbuhaler Ò and Diskus Ò (washout period 2-7 days). Terbutaline 0.5 mg/actuation via Turbuhaler Ò was used as reliever medication throughout. The primary endpoint was forced expiratory volume in 1 second (FEV 1) at 5 minutes post-dose. Secondary endpoints included proportion of patients achieving ‡12% increase in FEV 1 at 5 minutes post-dose.
A 49-year-old woman underwent a pneumonectomy because of a mass in the middle lobe. Histological ... more A 49-year-old woman underwent a pneumonectomy because of a mass in the middle lobe. Histological examination of the tumour showed a well-differentiated fetal adenocarcinoma (WDFA). This rare tumour appears to be associated with an excellent prognosis in the absence of metastases following surgical resection.
An otherwise healthy 44-yr-old man experienced a serious attack of bronchial obstruction after wo... more An otherwise healthy 44-yr-old man experienced a serious attack of bronchial obstruction after working with resins and hardeners, releasing fumes of a mixture of an alipathic and a cycloaliphatic diamine hardener. Eight hours after deliberate challenge with the hardener a large increase of airway resistance was found. Seventy-two hours after challenge, eosinophilia in the bronchoalveolar lavage (BAL) fluid together with a decrease of peripheral eosinophils was seen. After cessation of contact with this hardener, no more acute episodes occurred, although maintenance treatment with a topical corticosteroid and a beta 2-agonist remained necessary. A BAL performed 1 yr later showed a normal cell distribution. The results suggest that these aliphatic and cycloaliphatic diamine hardeners may be occupational hazards. Eosinophil inflammation may play a causal role.
Bronchial hyperresponsiveness (BHR) to methacholine and adenosine 5&amp;amp;#39;-monophosphat... more Bronchial hyperresponsiveness (BHR) to methacholine and adenosine 5&amp;amp;#39;-monophosphate (AMP) was studied in 15 allergic asthmatic patients before and 3 and 24 h after allergen challenge with house dust mite (HDM). Subjects attended the clinic on 3 consecutive days. On the first day a control solution was inhaled, and methacholine or AMP challenge was performed 3 h later. The next day HDM was inhaled, and 3 and 24 h later methacholine or AMP challenge was performed again. There were no significant difference in FEV1 baseline value between any of the study days. PD20 HDM, percentage decrease in FEV1, and AUC for both the EAR and LAR were not significantly different in the methacholine and AMP studies. After HDM challenge, PC20 methacholine decreased significantly from a geometric mean (+/- SEM) starting value of 1.39 +/- 0.63 mg/ml to 0.30 +/- 0.78 mg/ml (p less than 0.001) at 3 h and to 0.22 +/- 0.75 mg/ml (p less than 0.001) at 24 h. The magnitude of the decrease in PC20 methacholine at 3 h correlated with the severity of the late asthmatic reaction (LAR) as measured by the percentage fall in FEV1 and area under the curve (AUC) (r = -0.60 and r = 0.55; p less than 0.05). A significant decrease was observed in the PC20 AMP at 3 h, from a geometric mean value of 12.2 +/- 0.96 mg/ml after challenge with the control solution to 4.47 +/- 0.99 mg/ml (p less than 0.05) after HDM challenge.(ABSTRACT TRUNCATED AT 250 WORDS)
Severe asthma is characterized by persistent T-ceil activation, as demonstrated in both periphera... more Severe asthma is characterized by persistent T-ceil activation, as demonstrated in both peripheral blood and bronchial mucosa. Endobronchial biopsy specimens of patients with severe, corticosteroid-dependent asthma revealed increased expression of CD25+ on mucosal T cells. Increased immunoreactivity for IL-5 further supports the evidence that the inflammatory response is orchestrated by THSype T cells. Peripheral blood eosinophils and total serum IgE levels were increased in the absence of allergen and despite optimal treatment. The chemokine 1L-8 may also be an aggravating factor in severe asthma; as well as being a potent chemotaetic and activating factor for neutrophiIs, it may also be chemoattractant for eosinophils. We have recently detected increased levels of free IL-8 in the peripheral blood of patients with chlvnic severe asthma but not in healthy control subjects or in patients with mild asthma, even after allergen challenge. In patients with severe asthma there may be an imbalance between IL-8 production and the blocking capacity of IL-8 autoantibodies. Higher levels of IL-8 complexed to lgA autoantibody and increased numbers of activated T cells were also found in patients with unstable asthma compared with patients who had severe but stable disease. We conclude that IL-8 may provide an additional marker of asthma severity and corticosteroid responsiveness.
Bronchial hyperresponsiveness (BHR) to methacholine was studied in 14 patients with asthma andJiv... more Bronchial hyperresponsiveness (BHR) to methacholine was studied in 14 patients with asthma andJive healthy control subjects, with and without pretreatment with nedocromil sodium, 3 and 24 hours after allergen challenge. Eleven patients demonstrated a dual asthmatic response. A significant decrease in the provocative concentration causing a 20% fall in FEV, was found ffom a geometric mean starting value of I .I8 mglml on the control day to 0.24 mglml (p < 0.001) and to 0.17 mglml (p < 0.001) 3 and 24 hours afer allergen challenge. A significant correlation was observed between the increased BHR at 3 hours and the magnitude of the late response (r =-0.57; p < 0.05). Nedocromil sodium (6 mg) significantly inhibited the increase in BHR, 1 mglml (p < 0.001) at 3 hours and 0.50 mglml (p < 0.001) at 24 hours. Nedocromil sodium shifted the severity of the early allergic reaction (EAR) from mean-34.8% to-6.9% and inhibited the later allergic reaction (EAR) from-30.5% to + 0.4% (p < 0.005). From the study can be concluded that nedocromil sodium inhibits the EAR and LAR and the allergen-induced increase in BHR. The inhibitory effect of nedocromil sodium on the EAR may be related to its ability to inhibit the increased BHR before the development of the LAR. (JALLERGYCLINIMMINOL 1991;87:993-1001.) BHR, a characteristic feature of asthma, is related to the severity of the disease and the need for therapy. '3 * The precise link between symptoms, BHR, and airway inflammation is still uncertain.3, 4 BHR can be assessed by direct and indirect stimuli. It is supposed that the bronchoconstriction induced by methacholine results from direct stimulation of the smooth muscle itself.5 BHR increases in sensitized patients during natural exposure to airborne allergens or occupational allergens that induce asthma. Conversely, removal from environmental exposure to domestic or occupational allergens often results in a decreased BHR.6-9
To examine the role of the bronchial microvasculature and adhesion molecule expression in severe ... more To examine the role of the bronchial microvasculature and adhesion molecule expression in severe asthma, the authors have performed an immunohistochemical study on bronchial biopsies comparing 15 glucocorticoid-dependent asthmatics, 15 mild asthmatics and eight control subjects. Serially cut glycol methacrylate-embedded sections were stained with monoclonal antibodies identifying the vessel marker EN-4, intercellular adhesion molecule (I-CAM)-1, vascular cell adhesion molecule (VCAM)-1, E-and P-selectin. Sections were also stained for lymphocyte function associated antigen (LFA)-1 and very late antigen (VLA)-4. By comparison with mild asthma and nonasthma, severe asthma was characterized by increased numbers of submucosal vessels (p=0.009) which was associated with increased numbers of vessels expressing ICAM-1 (p=0.005). A highly significant correlation was found between the total number of EN-4+ vessels and the vessels expressing ICAM-1 (r=0.85, p=0.01). In contrast, E-selectin expression was lower in severe as compared with mild asthma (p=0.01) but not different from normal. No differences were found between the three groups in the expression of VCAM-1 and Pselectin nor in numbers of LFA-1+ and VLA-4+ cells. The results of this study support the notion that mucosal neovascularization is an important feature of airways remodelling in severe asthma. This is associated with a relatively higher density of vessels expressing intercellular adhesion molecule-1, although the expression of this adhesion molecule per vessel was not raised.
To improve our understanding of the inflammatory mechanisms undererlying severe disease, a biopsy... more To improve our understanding of the inflammatory mechanisms undererlying severe disease, a biopsy study was performed comparing 15 clinically unstable glucocorticoid-dependent asthmatics, 10 mild asthmatics, and 10 control subjects. Compared with mild asthma, severe asthma was characterized by reduced mucosal eosinophilia. Whilst no significant differences were found in the numbers of mast cells, neutrophils, CD3+ and CD4+ T-cells between the three groups, up to a 4-fold increase in the numbers of activated T-lymphocytes bearing the interleukin (IL)-2 receptor (IL-2R) was found in the mucosa in severe asthma compared to mild asthma (p=0.03) and control subjects (p=0.003). Compared to control subjects, the mucosa of severe asthmatics contained significantly (p=0.02) higher numbers of IL-5+ cells, with no differences between mild and severe disease. In contrast, staining for the anti-IL-4 monoclonal antibody 3H4 revealed that biopsies from mild asthmatics contained more IL-4+ cells than biopsies from severe asthmatics and control subjects (p=0.0008). In the severe asthmatics, a close correlation (r s =0.76, p=0.005) was found between the numbers of IL-2R-bearing cells and the variability in peak expiratory flow. In conclusion, persistent T-cell activation is a prominent feature of severe asthma. These results also indicate that interleukin-5, and not interleukin-4, is upregulated in severe disease.
The extent of epithelial injury in asthma is reflected by expression of the epidermal growth fact... more The extent of epithelial injury in asthma is reflected by expression of the epidermal growth factor receptor (EGFR), which is increased in proportion to disease severity and is corticosteroid refractory. Although the EGFR is involved in epithelial growth and differentiation, it is unknown whether it also contributes to the inflammatory response in asthma. Because severe asthma is characterized by neutrophilic inflammation, we investigated the relationship between EGFR activation and production of IL-8 and macrophage inhibitory protein-1 alpha (MIP-1alpha) using in vitro culture models and examined the association between epithelial expression of IL-8 and EGFR in bronchial biopsies from asthmatic subjects. H292 or primary bronchial epithelial cells were exposed to EGF or H2O2 to achieve ligand-dependent and ligand-independent EGFR activation; IL-8 mRNA was measured by real-time PCR and IL-8 and MIP-1alpha protein measured by enzyme-linked immunosorbent assay (ELISA). Epithelial IL-8 and EGFR expression in bronchial biopsies from asthmatic subjects was examined by immunohistochemistry and quantified by image analysis. Using H292 cells, EGF and H2O2 increased IL-8 gene expression and release and this was completely suppressed by the EGFR-selective tyrosine kinase inhibitor, AG1478, but only partially by dexamethasone. MIP-1alpha release was not stimulated by EGF, whereas H2O2 caused a 1.8-fold increase and this was insensitive to AG1478. EGF also significantly stimulated IL-8 release from asthmatic or normal primary epithelial cell cultures established from bronchial brushings. In bronchial biopsies, epithelial IL-8, MIP-1alpha, EGFR and submucosal neutrophils were all significantly increased in severe compared to mild disease and there was a strong correlation between EGFR and IL-8 expression (r = 0.70, P &lt; 0.001). These results suggest that in severe asthma, epithelial damage has the potential to contribute to neutrophilic inflammation through enhanced production of IL-8 via EGFR- dependent mechanisms.
American Journal of Respiratory and Critical Care Medicine, 1997
We have tested the hypothesis that the expression of interleukin-8 (IL-8) is increased in bronchi... more We have tested the hypothesis that the expression of interleukin-8 (IL-8) is increased in bronchial tissue and circulating leukocytes of atopic asthmatics, indicating a role for this chemokine in asthma. The concentration of IL-8 in its free form and complexed with IgG or IgA was measured by ELISA in bronchial tissue, serum, and lysates of freshly isolated peripheral blood mononuclear cells and granulocytes from subjects with mild or severe asthma and nonatopic nonasthmatic subjects. Serum ECP was measured by fluorescent enzyme immunoassay. Free IL-8 was detected in the sera (n = 44) and bronchial tissue (n = 9) of all subjects with severe atopic asthma, but it was undetectable in normal subjects and subjects with mild atopic asthma, suggesting that free IL-8 is a marker of severe asthma. A positive correlation between free IL-8 and serum ECP levels found in severe disease suggests that IL-8 is associated with eosinophil activation. Complexes of IL-8 with IgA and IgG were detected in all serum and tissue samples. However, the levels of the IL-8-IgA complex were increased in the bronchial mucosa in asthma, and in blood were related to disease activity. Together, these results point to upregulation of IL-8 production in asthma and the induction of IL-8 binding immunoglobulins of the IgA class in the inflamed mucosa. We suggest a proinflammatory role for these complexes in lung tissue.
American Journal of Respiratory and Critical Care Medicine, 1994
The long-acting beta 2-agonist salmeterol has been suggested to have other pharmacologic activiti... more The long-acting beta 2-agonist salmeterol has been suggested to have other pharmacologic activities, that is, antiinflammatory capacities, in addition to its bronchodilator properties. We investigated the protective effect of 50 micrograms salmeterol in a placebo-controlled study on house dust mite-induced early- and late-phase reactions in 19 atopic asthmatic subjects. FEV1 and methacholine airway reactivity (AR) were measured. Eosinophils and their activation markers in peripheral blood were counted as indirect parameters of inflammation. Corrections were made for confounding of bronchodilator effects by salmeterol and the spontaneous diurnal variation, using saline inhalation as a control. Salmeterol completely inhibited the fall in FEV1 up to 10 h after the house dust mite challenge. Nevertheless, after correction, a biphasic response was present in the salmeterol group. Salmeterol protected against the allergen-associated increase in AR 3 h after the challenge, but no protection was observed after 24 h. Salmeterol did not inhibit the allergen-induced changes in total number of eosinophils and their activation markers in peripheral blood. These data suggest that a single dose of salmeterol modifies allergen-induced airway responses, above all by sustained bronchodilation.
The phenotypic cellular profile of bronchial lavage (BL) and bronchoalveolar lavage (BAL) was stu... more The phenotypic cellular profile of bronchial lavage (BL) and bronchoalveolar lavage (BAL) was studied in 7 single early (SR) and 10 dual asthmatic responders (DR). Lavage was performed, after previously having determined bronchial hyperresponsiveness to histamine and the response to house dust mite (HDM) challenge. The recovered lavage fluid was separated in two fractions, BL and BAL. Total fluid recovery and cell number from the BL and BAL were comparable in both patient groups. Differential cell counting and immunocytochemistry were performed. DR had a significantly higher number of eosinophils and EG2+ cells in BL but not in their BAL. No differences could be found in CD4+, CD8+, and HLA-DR+ cells. A strong correlation was found between eosinophils in the BL+ and EG2+ cells in the BL (r = 0.79, p &lt; 0.001) and between eosinophils in the BL and peripheral blood eosinophils (r = 0.70, p &lt; 0.0025). The number of EG2+ cells and the number of epithelial cells in both BL and BAL showed a correlation (r = 0.55, p &lt; 0.05). Dual responders had a higher total IgE (p &lt; 0.01), and total serum IgE correlated well with the eosinophils in the BL (r = 0.85, p &lt; 0.0001). Our observations demonstrate cellular differences in the lung on mainly a bronchial level between single early and dual asthmatic responders. A bronchial lavage eosinophil and EG2+ cell count and higher blood total IgE level are associated with the tendency to develop a dual asthmatic response.
Low-dose methotrexate treatment in severe glucocorticoid-dependent asthma: effect on mucosal infl... more Low-dose methotrexate treatment in severe glucocorticoid-dependent asthma: effect on mucosal inflammation and in vitro sensitivity to glucocorticoids of mitogen-induced T-cell proliferation.
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Papers by Rene Aalbers