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S R Durham

Publications and source records attributed to S R Durham.

At least 109 records · Page 6Linked to original sources

IL-4 and IL-5 mRNA and protein in bronchial biopsies from patients with atopic and nonatopic asthma: evidence against "intrinsic" asthma being a distinct immunopathologic entity.

Intrinsic (nonatopic) asthma is considered to be a distinct pathogenetic variant of asthma since, unlike extrinsic (atopic) asthma, patients with the disease are skin test-negative to common aeroallergens, and have total serum IgE concentrations within the normal range. Nevertheless, the recent demonstration of increased numbers of cells expressing the high-affinity IgE receptor in bronchial biopsies from atopic and nonatopic asthmatic subjects, together with epidemiologic evidence indicating that serum IgE concentrations relate closely to asthma prevalence regardless of atopic status, suggests that IgE-mediated mechanisms may participate in the pathogenesis of both atopic and nonatopic asthma. Furthermore both variants of the disease are associated with bronchial mucosal eosinophilic inflammation. Interleukin-4 (IL-4) is an essential cofactor for IgE synthesis, and there is strong evidence that IL-5 plays a major role in eosinophil accumulation in asthmatic inflammation. For these reasons we compared the expression of IL-4 and IL-5 mRNA and protein product using a semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) amplification, in situ hybridization, and immunohistochemistry in bronchial biopsies from symptomatic atopic and nonatopic asthmatic subjects and atopic and nonatopic controls. The results showed that as compared with controls, biopsies from both groups of asthmatic subjects had increased numbers of IL-4 and IL-5 mRNA copies relative to beta-actin mRNA as detected by RT-PCR. Similarly, in situ hybridization and immunohistochemistry demonstrated increased numbers of cells expressing IL-4 and IL-5 mRNA and protein in asthmatic subjects, irrespective of their atopic status. We conclude that individuals with either atopic or nonatopic asthma show infiltration of the bronchial mucosa with cells expressing Th2-type cytokines, providing further evidence for similarities in the immunopathogenesis of these clinically distinct forms of asthma.

Adult↗

Increased expression of mRNA encoding RANTES and MCP-3 in the bronchial mucosa in atopic asthma.

The selective recruitment of eosinophils into the mucosal lining of the airways is a prominent feature of atopic asthma, and is believed to be an important component in the disease pathogenesis. The precise stimuli responsible for the influx of eosinophils remain unclear. Using a semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) technique, the numbers of copies (relative to the "housekeeping" gene beta-actin) of messenger ribonucleic acid (mRNA) encoding the eosinophil-active chemotactic cytokines, the factor regulated upon activation in normal T-cells expressed and secreted (RANTES) and monocyte chemotactic protein-3 (MCP-3), was measured in bronchial biopsies from atopic asthmatic patients (n = 9), and compared with atopic nonasthmatic (n = 8) and nonatopic nonasthmatic (n = 8) control subjects. In addition, further biopsies from each subject were prepared for immunohistochemistry and the numbers of activated (EG2+) eosinophils measured. The expression of RANTES mRNA was significantly elevated in the atopic asthmatic group as compared to the atopic nonasthmatic controls (p = 0.013) and the nonatopic nonasthmatic controls (p = 0.007). Similarly, the expression of mRNA encoding MCP-3 was significantly elevated in the atopic asthmatic group, relative to the atopic nonasthmatic controls (p = 0.014) and the nonatopic nonasthmatic control group (p = 0.011). Elevated RANTES and MCP-3 mRNA expression was associated with significantly increased numbers of bronchial mucosal eosinophils in the atopic asthmatic patients as compared to the atopic nonasthmatic (p = 0.03) and nonatopic nonasthmatic (p = 0.006) control subjects. In conclusion, we have identified elevated expression of messenger ribonucleic acid encoding RANTES and monocyte chemotactic protein-3 in the bronchial mucosa of atopic asthmatic patients relative to controls. These findings are compatible with the hypothesis that eosinophil-active beta-chemokines play a role in the mechanism of eosinophil recruitment to the asthmatic bronchial mucosa.

Actins↗

A comparison of the effects of oral cetirizine and inhaled beclomethasone on early and late asthmatic responses to allergen and the associated increase in airways hyperresponsiveness.

BACKGROUND: Cetirizine is a non-sedating H1 antihistamine which is effective in the treatment of allergic rhinitis and urticaria. It inhibits eosinophil and basophil chemotaxis in late cutaneous allergic reactions in skin windows. Its effect on early (EAR) and late asthmatic reactions (LAR) is less certain. METHODS: We examined the effect on EAR and LAR of 3 days treatment with oral cetirizine (15 mg twice daily) compared with a single dose of inhaled beclomethasone 10 min prior to allergen challenge in a placebo-controlled (oral and inhaled) double-blind cross-over design with three treatment arms separated by 14 days. RESULTS: Cetirizine did not significantly inhibit either the EAR or LAR documented by maximum percentage fall in FEV1 (0-3 and 6-9 h) or as area under the curve (AUC between 0 and 3 and 6-9 h). Beclomethasone inhibited the LAR compared with placebo (P = 0.02) when expressed as AUC (6-9 h). This did not quite reach statistical significance (P = 0.06) when expressed as maximal percentage late fall in FEV1 between 6 and 9 h. A greater than twofold increase in airways responsiveness to methacholine was observed 3 h after challenge which was significantly reduced by beclomethasone compared with placebo (P < 0.02) and cetirizine (P < 0.05). The data suggest that oral cetirizine does not significantly inhibit either the EAR or LAR. Beclomethasone inhibited both the early increase in airways responsiveness and the subsequent LAR. Our study also confirms the view that early increases in airway responsiveness precede the late response and suggests that these associated events are not dissociable by the pharmacological treatments employed in this study.

Administration, Inhalation↗

Identification of messenger RNA for IL-4 in human eosinophils with granule localization and release of the translated product.

Human eosinophils are cytokine-producing cells that are prominent in IgE-dependent allergic tissue reactions. IL-4 promotes the development of the Th2-type phenotype in T cells and is an essential cofactor for IgE production by B cells. We detected mRNA for IL-4 by reverse transcription-PCR in blood eosinophils from atopic asthmatics. By specific ELISA, 108 +/- 20 pg of IL-4 protein/10(6) cells could be extracted from whole cells, and approximately 30% of the IL-4 was released after incubation with serum-coated particles. Using immunocytochemistry, eosinophils from atopic asthmatics and nonatopic controls showed IL-4 immunoreactivity using an anti-IL-4 mAb. IL-4 was located predominantly in the eosinophil granules, as shown by both immunogold electron microscopy and a cell fractionation technique that dissociated cell granules from membrane and cytosolic components. IL-4 mRNA colocalized with eosinophils (using sequential immunocytochemistry with an eosinophil-specific (EG2) mAb and in situ hybridization using an IL-4-specific antisense riboprobe) in both cell cytospins from bronchoalveolar lavage fluid from asthmatics as well as skin biopsies obtained from allergen-induced late phase (6-h) reactions in atopic subjects. Using double immunocytochemistry on skin biopsies with eosinophil- and IL-4-specific mAb, 83.5 +/- 3.5% of eosinophils were IL-4+. Conversely, eosinophils accounted for 46.5 +/- 3.9% of the total cells expressing IL-4 immunoreactivity. Thus, human eosinophils express mRNA for IL-4, and the translated product is contained within the crystalloid granule from which it is released after stimulation with serum-coated particles. These observations are consistent with the hypothesis that eosinophils contribute to the development of the Th2 phenotype by T cells infiltrating atopic allergic reactions as well as to IgE synthesis.

Asthma↗

New insights into the mechanisms of immunotherapy.

Allergen-specific immunotherapy retains a place in treatment in patients with allergic rhinitis who fail to respond to conventional treatment with antihistamines and topical corticosteroids. Studies on mechanisms of immunotherapy have previously focussed on changes in serum antibodies, including blunting of seasonal rises in specific IgE and increase in "blocking" specific IgG antibodies. Immunotherapy in patients with rhinitis has also been shown to inhibit effector cells with a decrease in nasal mucosal eosinophils and epithelial mast cells. Recent evidence suggests that these events may be orchestrated by an effect of immunotherapy on T lymphocytes with alteration from a predominant "Th2" response (interleukin 4 and 5) in favour of an additional "Th1" response (gamma interferon) which may decrease tissue eosinophilia and local IgE production. Novel therapeutic approaches to allergic diseases might include use of topical gamma interferon, immunosuppressive agents, anti-CD4 antibodies or strategies directed specifically against IL-4 or IL-5.

Adjuvants, Immunologic↗

Liposome-mediated CFTR gene transfer to the nasal epithelium of patients with cystic fibrosis.

We report the results of a double-blind, placebo-controlled trial in nine cystic fibrosis (CF) subjects receiving cationic liposome complexed with a complementary DNA encoding the CF transmembrane conductance regulator (CFTR), and six CF subjects receiving only liposome to the nasal epithelium. No adverse clinical effects were seen and nasal biopsies showed no histological or immuno-histological changes. A partial restoration of the deficit between CF and non-CF subjects of 20% was seen for the response to low Cl- perfusion following CFTR cDNA administration. This was maximal around day three and had reverted to pretreatment values by day seven. In some cases the response to low Cl- was within the range for non-CF subjects. Plasmid DNA and transgene-derived RNA were detected in the majority of treated subjects. Although these data are encouraging, it is likely that transfection efficiency and the duration of expression will need to be increased for therapeutic benefit.

Base Sequence↗

Eosinophil cationic protein (ECP) and eosinophil protein X (EPX) concentrations in serum and bronchial lavage fluid in asthma. Effect of prednisolone treatment.

BACKGROUND: Eosinophil granule proteins may contribute to bronchial hyperresponsiveness in asthma. OBJECTIVE: To measure eosinophil cationic protein (ECP) and eosinophil protein X (EPX) in serum and bronchial lavage fluid from 20 asthmatics and 16 control subjects. To assess the effect on these eosinophil proteins of corticosteroid treatment of asthma. To determine whether serum ECP and EPX measured weekly in a longitudinal study for 10 weeks reflected changes in lung function. METHODS: Eosinophil granule proteins were measured by radioimmunoassay of bronchial wash (BW), bronchoalveolar lavage (BAL) and serum. RESULTS: Eosinophils were elevated in BAL (P < 0.01), BW (P < 0.01) and blood (P < 0.01) from asthmatics compared with control subjects. Eosinophils cationic protein concentration was significantly elevated in BAL (P < 0.05) and BW from asthmatics (P < 0.01) and EPX was increased in BAL (P < 0.05) and BW (P < 0.01). These changes were also reflected in elevated serum ECP (P < 0.01) and EPX (P < 0.01) concentrations in asthmatic subjects. There was no significant difference between subjects receiving prednisolone and the placebo group, but there was a fall in ECP in BW (P < 0.05) and serum (P < 0.01) and in EPX in BW (P < 0.01) and serum (P < 0.01) within the group receiving prednisolone. In the longitudinal study there was only a significant difference between ECP values associated with highest and lowest peak expiratory flow rate (PEFR) (P < 0.05). CONCLUSIONS: These data confirm a role for eosinophil activation in the airway in asthma pathogenesis, and add some support to the hypothesis that corticosteroids may inhibit eosinophil activation in asthma.

Adult↗

Grass pollen immunotherapy: efficacy and safety during a 4-year follow-up study.

Grass pollen immunotherapy is effective, although efficacy must be balanced against side-effects. In a double-blind, placebo-controlled trial of 40 adult patients with summer hay fever, immunotherapy with a depot grass pollen extract (Phleum pratense, Alutard SQ) reduced symptoms and medication requirements with an acceptable minimal level of side-effects (31). The original placebo group, as well as the actively treated group, have now received active immunotherapy in an open fashion for a further 3 years. An important question was whether continued injection treatment was accompanied by maintained clinical improvement. By analysis of diary symptoms, rescue medication, and visual analogue scores during the pollen season, we show that efficacy was maintained throughout the 3-4-year study period. Clinical improvement was accompanied by a sustained and marked decrease in immediate conjunctival allergen sensitivity and a further significant decrease in the size of the allergen-induced late cutaneous response. In contrast, an initial decrease in the allergen-induced immediate cutaneous response was not maintained at 3-4 years. Of the patients, 37/40 completed the first year, 33/40 the second year, and 32/40 the third year of treatment. Patients dropped out for reasons other than the outcome of immunotherapy. During a total of 2598 injections, five immediate systemic reactions were observed, all during the induction (not maintenance) phase, and all occurred within 10 min of injection and responded promptly to adrenaline. Grass pollen immunotherapy is effective and safe, provided it is performed on carefully selected patients by trained physicians with immediate access to resuscitative measures.

Adult↗

Phenotype of cells expressing mRNA for TH2-type (interleukin 4 and interleukin 5) and TH1-type (interleukin 2 and interferon gamma) cytokines in bronchoalveolar lavage and bronchial biopsies from atopic asthmatic and normal control subjects.

We investigated the phenotype of cells expressing messenger RNA encoding interleukin 4 (IL-4), IL-5, IL-2, and interferon gamma (IFN-gamma) in bronchoalveolar lavage (BAL) and bronchial biopsies (BX) from seven mild atopic asthmatic patients and nine nonasthmatic controls. Immunocytochemistry followed by in situ hybridization using either 35S- or digoxigenin-labeled riboprobes was performed on cytospins from BAL and BX, respectively. With BAL or BX, in situ hybridization alone showed significant increases in percentages of IL-2, IL-4, and IL-5 mRNA+ cells when asthmatics were compared to nonasthmatic controls. Double immunocytochemistry-in situ hybridization revealed that > 70% of IL-4 and IL-5 mRNA+ cells were activated T cells (CD3+). The remaining IL-4 and IL-5 mRNA+ signals were colocalized to tryptase+ mast cells, and activated eosinophils (EG2+). Rare IL-4 and IL-5 mRNA+ cells were observed in nonasthmatic controls, the majority being CD3+ cells, as were IL-2 and IFN-gamma mRNA+ cells (in both asthmatics and controls). A few IL-4 (< 8%) and IL-5 (< 5%) mRNA+ signals did not colocalize with any of the cells identified by immunocytochemistry. Thus, we provide further evidence that CD3+ T cells are the most abundant cells expressing IL-4 and IL-5 mRNA in BAL and BX from allergic asthma. Fewer, but detectable, numbers of tryptase+ mast cells and EG2+ eosinophils also expressed these transcripts.

Adult↗

Kinetics of cell infiltration and cytokine messenger RNA expression after intradermal challenge with allergen and tuberculin in the same atopic individuals.

BACKGROUND: Previous studies, in which one time point was used, have shown that cells infiltrating skin biopsy specimens taken during allergen-induced late-phase responses (LPR) had a TH2-like (interleukin-4 [IL]-4 and IL-5 mRNA+) cytokine profile, whereas in delayed-type hypersensitivity (DTH) there was a predominant TH1-type pattern. OBJECTIVE: The study was designed to examine the kinetics of accumulation of inflammatory cells and cells expressing mRNA for TH2- or TH1-type cytokines in LPR and DTH elicited simultaneously in the same subjects. METHODS: Immunocytochemistry (alkaline phosphatase anti-alkaline phosphatase technique) and in situ hybridization were used to analyze skin biopsy specimens taken during allergen-induced LPR. RESULTS: In LPR elevated numbers of CD3+ and CD4+ cells, eosinophils, neutrophils, and IL-4 and IL-5 mRNA+ cells were detected as early as 1 hour after allergen challenge, with a peak at 6 hours, which was maintained for up to 96 hours. A small but significant delayed increase in macrophages, CD8+ and CD25+ cells, and IL-2 and interferon-gamma mRNA+ cells was also observed, but only at the 48-hour and 96-hour time points. In contrast, in DTH the numbers of CD3+, CD4+, and mRNA+ cells for IL-2 and interferon-gamma were not elevated until 24 hours after challenge and peaked at 48 hours after injection. At 48 hours there was an additional small but significant increase in IL-4 and IL-5 mRNA+ cells. For both LPR and DTH the kinetics of the increases in inflammatory cells and cytokine mRNA-expressing cells paralleled the clinical response. CONCLUSIONS: In LPR accumulation of T cells and granulocytes, together with cells expressing mRNA encoding for TH2-type cytokines, is relatively rapid (i.e., within 1 to 6 hours), whereas in DTH the T cell/macrophage infiltration and appearance of cells expressing TH1-type cytokines are not apparent until 24 to 48 hours. In LPR there is a TH1-type (or possibly TH0) component at 48 to 96 hours, and in DTH there is an additional TH2/TH0 response.

Adolescent↗

Influence of prolonged treatment with topical corticosteroid (fluticasone propionate) on early and late phase nasal responses and cellular infiltration in the nasal mucosa after allergen challenge.

We have examined the effect of prolonged treatment with topical corticosteroid on allergen-induced early and late nasal responses and the associated inflammatory cell infiltrate in grass pollen sensitive allergic rhinitics. Following a randomized double-blind 6 week treatment period with fluticasone propionate 200 micrograms aqueous nasal spray twice daily or matched placebo spray, nasal provocation was performed using Timothy grass pollen extract. Nasal symptoms were recorded at intervals from 0 to 24 h. Nasal biopsies were performed before treatment and at 24 h after allergen and processed for immunohistology. When corticosteroid-treated patients were compared with the placebo group there was an approximately 50% decrease in the size of the early (0-60 min) response and almost complete inhibition of late (1-24 h) nasal symptoms after allergen challenge. After allergen challenge markedly fewer T lymphocytes and CD25+ (interleukin-2 receptor bearing) cells were observed in both the epithelium and submucosa in fluticasone treated patients compared with the placebo group. Significantly less total and activated eosinophils were observed, particularly within the nasal epithelium. Submucosal mast cell counts were decreased, whereas increased numbers of submucosal neutrophils were observed. These results confirm that topical corticosteroid treatment inhibits allergen-induced early and late nasal responses. This may possibly occur following a decrease in T lymphocytes and/or mast cells and their products and a consequent reduction in tissue eosinophilia.

Administration, Topical↗

Rhinitis, sinusitis and the yellow nail syndrome: a review of symptoms and response to treatment in 17 patients.

A total of 17 patients with yellow nail syndrome are described. Their symptoms, age of onset and severity are examined with particular reference to the presence of rhinosinusitis. Fourteen of the patients (83%) suffered severe rhinosinusitis, which pre-dated nail changes in four, coincided with yellow nails in six, and occurred later in the remaining patients. In general, patients responded poorly to conventional medical and surgical treatment, with the exception of functional endoscopic sinus surgery (FESS) which may be of value in these patients. The frequent association of rhinosinusitis with yellow nails may warrant its recognition as part of the syndrome. Careful inspection of the fingernails in all patients presenting with severe rhinosinusitis is warranted.

Adolescent↗

Topical glucocorticosteroid (fluticasone propionate) inhibits cells expressing cytokine mRNA for interleukin-4 in the nasal mucosa in allergen-induced rhinitis.

Allergen-induced late nasal responses are associated with recruitment and activation of T lymphocytes and eosinophils and preferential mRNA expression for T-helper type 2 (Th2) cytokines. We tested the hypothesis that topical corticosteroids may inhibit late responses by inhibiting cells expressing mRNA for Th2 cytokines. A randomized double-blind placebo-controlled trial of topical corticosteroid (fluticasone propionate) was performed in 48 adult grass pollen-sensitive patients. Nasal biopsies were taken at baseline and repeated 24 hr after local nasal allergen provocation following 6 weeks treatment with either fluticasone propionate 200 micrograms or placebo nasal spray twice daily. Baseline mRNA expression for interleukin-4 (IL-4) (P = 0.01) and IL-5 (P = 0.002) was higher in the patients than in normal controls. Topical corticosteroid treatment significantly inhibited immediate nasal symptoms, with almost complete inhibition of the late response following allergen challenge. This was associated with a marked decrease in the allergen-induced increases in cells expressing mRNA for IL-4 (P = 0.002) but not for IL-5. Inhibition of the late response was also accompanied by decreases in CD25+ cells, presumed T lymphocytes and eosinophils. A significant correlation was observed between the decreases in IL-4 mRNA+ cells and in eosinophils after treatment (r = 0.46, P < 0.05). These results suggest that prolonged treatment with topical corticosteroid inhibits allergen-induced early and late nasal responses and the associated tissue eosinophilia, and that, at least in part, this may result from inhibition of cells expressing mRNA for IL-4.

Administration, Topical↗

T lymphocytes and mast cells express messenger RNA for interleukin-4 in the nasal mucosa in allergen-induced rhinitis.

We have investigated the phenotype of interleukin-4 (IL-4) mRNA+ cells in the nasal mucosa of six subjects with allergic rhinitis before and 24 hr after local allergen provocation with grass pollen extract. Serial cryostat sections were cut from paraformaldehyde-fixed snap-frozen nasal biopsies, and immunocytochemistry (APAAP) followed by in situ hybridization performed on the same sections. For immunocytochemistry, antibodies against CD3, tryptase, major basic protein (MBP) and CD68 were used to identify T cells, mast cells, eosinophils and macrophages, respectively. Hybridization studies were performed using a digoxigenin-labelled IL-4 riboprobe. Nitroblue tetrazolium (NBT) and X-phosphate-5-bromo-4-chloro-3-indoly phosphate (BCIP) served as chromogens to detect hybridization IL-4 mRNA signals. Significant increases in T lymphocytes and eosinophils and in the number of IL-4 mRNA+ cells were observed after allergen challenge. Double immunocytochemistry/in situ hybridization demonstrated that the majority of IL-4 mRNA+ cells after allergen challenge were CD3+ (73.7% +/- 1.6). Lower numbers of IL-4 mRNA hybridization signals were co-localized to tryptase+ cells (26.0% +/- 1.6). In contrast, no IL-4 mRNA hybridization signals were co-localized to either eosinophils or macrophages. These results indicate that after allergen challenge T cells are the principal cellular source of IL-4 mRNA transcripts during human late nasal responses, with a lesser contribution from mast cells.

Adult↗

Expression of endothelial and leukocyte adhesion molecules interacellular adhesion molecule-1, E-selectin, and vascular cell adhesion molecule-1 in the bronchial mucosa in steady-state and allergen-induced asthma.

BACKGROUND: Interactions between cell adhesion molecules and their ligands are an integral part of inflammatory processes and may have direct relevance to the pathology of asthma. METHODS: Immunostaining with antibodies to cell adhesion molecules was performed on bronchial biopsy specimens from persons with intrinsic and extrinsic asthma, normal nonasthmatic control subjects, and patients with asthma after allergen challenge. RESULTS: There was constitutive expression of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) in patients with intrinsic and extrinsic asthma and in control subjects. Compared with control subjects, ICAM-1 and E-selectin staining in the submucosa was greater in the intrinsic asthmatic group for intensity (p < 0.02, p < 0.05) and extent (p < 0.01, p < 0.05) of staining, respectively. No differences were observed between patients with extrinsic asthma and normal control subjects, and VCAM-1 expression did not differ among the groups. Epithelial expression of ICAM-1 was more frequent in patients with asthma compared with normal control subjects (p < 0.05). Compared with diluent challenge, bronchial biopsy specimens obtained 24 hours after allergen challenge revealed no significant differences in intensity or extent of staining for ICAM-1, E-selectin, or VCAM-1. After allergen challenge, the intensity and extent of both VCAM-1 and ICAM-1 expression correlated significantly with the number of eosinophils (cells positive for major basic protein). Epithelial ICAM-1 expression was more frequently observed after allergen challenge than after diluent challenge (p < 0.02). CONCLUSIONS: The data suggest a complex pattern of regulation for ICAM-1, E-selectin, and VCAM-1 in vivo, where they may reflect the degree of ongoing inflammation in asthma.

Adult↗

Relationships among numbers of bronchoalveolar lavage cells expressing messenger ribonucleic acid for cytokines, asthma symptoms, and airway methacholine responsiveness in atopic asthma.

BACKGROUND: We recently demonstrated that T lymphocytes in bronchoalveolar lavage (BAL) fluid from atopic asthmatic patients were activated and expressed increased cytokine messenger ribonucleic acid (mRNA) for "TH2-type" cytokines, particularly IL-4 and IL-5, when compared with those in normal control subjects. This pattern of cytokines may determine the nature of the cellular infiltrate in the bronchial mucosa in asthma and hence the bronchial hyperresponsive (BHR) and symptoms that characterize this condition. METHODS: To examine the association between these cytokines and clinical measures of asthma severity we have extended our studies of BAL cells from subjects with atopic asthma. Numbers of BAL cells with positive in situ hybridization signals for IL-2, IL-3, IL-4, IL-5, granulocyte macrophage colony-stimulating factor (GM-CSF), and interferon-gamma were counted on cytocentrifuge preparations. Results were compared between patients with symptomatic (n = 19) and asymptomatic asthma (n = 10), and associations were sought with airway methacholine responsiveness, resting airway caliber, and asthma symptom scores. RESULTS: There were increased proportions of cells positive for IL-3 (p < 0.05), IL-4 (p < 0.005), IL-5 (p < 0.005), and GM-CSF (p < 0.005) mRNA in BAL fluid from patients with symptomatic asthma when compared with that from subjects free of symptoms, but no difference between the groups in numbers of cells expressing IL-2 and interferon-gamma mRNA. There were significant associations among numbers of cells expressing mRNA for IL-4, IL-5, and GM-CSF, and airflow restriction, BHR, and Aas asthma score. CONCLUSIONS: These findings support the hypothesis that cytokines contribute to airway events that determine asthma symptoms and BHR.

Adult↗

Activation of CD4+ T cells, increased TH2-type cytokine mRNA expression, and eosinophil recruitment in bronchoalveolar lavage after allergen inhalation challenge in patients with atopic asthma.

BACKGROUND: We have examined whether the local eosinophilia provoked by inhalational allergen challenge of patients with atopic asthma is associated with the appearance, in vivo, of activated TH2-type T helper lymphocytes. METHODS: Fifteen patients with atopic asthma had bronchial wash and bronchoalveolar lavage (BAL) 24 hours after allergen or diluent challenge separated by at least 21 days. RESULTS: There was an increase in eosinophils in both bronchial wash (p = 0.01) and BAL (p = 0.02) after allergen challenge but not after diluent challenge. Activation of CD4+ BAL T cells was suggested by an increase in the expression of CD25 shown by flow cytometry after allergen challenge, when compared with diluent (p = 0.02). There was no evidence of activation of CD8 T cells. By in situ hybridization after allergen challenge as compared with diluent, increases were shown in the numbers of cells expressing mRNA for interleukin-4 (IL-4) (p = 0.005), IL-5 (p = 0.01), and granulocyte-macrophage colony-stimulating factor (p = 0.03) but not IL-3, IL-2, or interferon-gamma. In situ hybridization of BAL cells after immunomagnetic separation of CD2-positive and CD2-negative cell populations showed that IL-4 and IL-5 mRNAs were associated with T lymphocytes after allergen challenge. BAL and bronchial wash eosinophilia closely correlated with maximal late fall in forced expiratory volume in 1 second after allergen challenge. CONCLUSION: Cytokines produced by activated TH2-type CD4+ T cells in the airway may contribute to late asthmatic responses by mechanisms that include eosinophil accumulation.

Administration, Inhalation↗