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Notes: Thirty-seven patients with a history of systemic anaphylactic stings were desensitized by the rush method. Patients were evaluated by skin testing twice, before and 6 weeks after desensitization. An additional control group of 10 patients, not yet desensitized, were tested for skin test technique reproducibility at 6-week intervals. Results were compared with IgE and IgG antibody levels, and with platelet reactivity towards specific Hymenoptera venom. Before desensitization, the maximum skin-test sensitivity was observed at 10−5μg venom/ml in 56% of patients and decreased to 10−1μg venom/ml after desensitization (48·6% of patients). Decrease of cutaneous tests was observed in 28/37 patients (75%) (P 〈 0·001) and was not associated with significant variations of specific IgE or IgG antibody levels, but was correlated with the decrease of platelet reactivity (P 〈 0·05). Conversely, variations of skin-test sensitivity in the control group was not significant.

Notes: Background Interleukin-8 (IL-8) is a chemotactic cytokine for neutrophils and primed eosinophils. In allergic rhinitis, allergen exposure triggers leucocyte recruitment.Objective We evaluated in this study IL-8 secretion and the neutrophil chemotactic activity in nasal lavages collected after a nasal allergen challenge. Moreover, the participation of IL-8 in the neutrophil chemotactic activity was quantified.Methods Four healthy subjects and 19 patients with allergic rhinitis were exposed to a nasal allergen challenge. As a control, saline challenge was performed in four patients with allergic rhinitis. Concentration of IL-8 was measured hy ELISA in nasal lavages collected before and after challenge. Neutrophil chemotactic assay was developed using a 48-well chemotaxis microassembly.Results After allergen challenge, the healthy subjects, the four patients receiving saline and one patient exposed to allergen did not respond; seven patients presented a single early reaction and 11 patients a dual response. For healthy subjects and the four patients exposed to saline, the level of IL-8 did not increase after challenge in comparison with that at baseline. After allergen challenge, two peaks of IL-8 release were observed for patients with allergic rhinitis during the early (30 min to 1 h 30 min) and the late periods (3 h 30 min to 9 h 30 min), however the difference was not significant for the early period. During the late period, a significant increase in IL-8 concentrations was detected for the patients developing a dual response, whereas the difference was not significant for those presenting only an early reaction. The neutrophil chemotactic activity of nasal lavages from patients with allergic rhinitis collected during the early and the late reactions (17 ± 2.1 and 23.3 ± 2.8 neutrophils per high power field (hpf), respectively) was significantly higher than the activity of lavage fluid collected at haseline (9.2 ± 1.8 neutrophils per hpf). Nevertheless, the addition of a neutralizing anti-IL-8 antibody inhibited weakly the chemotactic activity of lavage fluid from rhinitic patients collected during the early or the late periods (18 and 11% of inhibition) (P= NS).Conclusion These data show that allergen challenge increased significantly the secretion of IL-8 for the patients with allergic rhinitis. However, neutralization of IL-8 in nasal lavages by a specific antibody revealed that the role of this chemokine in granulocyte infiltrate was limited, suggesting that IL-8 acts in connection with other chemotactic factors in this recruitment.

Notes: Background Recognition of antigen bound to the major histocompatibility complex by the T cell receptor is insufficient to lead to T cell proliferation and effector function, which require co-stimulatory signals, such as those resulting from the interaction of CD28 expressed on T lymphocytes and CD80/CD86 expressed on APCs. Lack of interaction between these accessory molecules during antigen stimulation leads to a state of antigen-specific lymphocyte unresponsiveness. Previous studies have shown that rush venom immunotherapy decreases venom-specific T cell proliferation very early after the initiation of the rush.Objective In order to see whether this hyporeactivity was associated with a down regulation of accessory molecules, we studied CD28 surface expression on T lymphocytes from 10 non-atopic controls and from 10 non-atopic patients undergoing rush venom immunotherapy.Methods Peripheral blood samples were collected before the rush (day 0), at the end of the rush (day 1), at day 15 and at day 45. CD28 expression was analysed using flow cytometry with double labelling of the CD4+ and CD8+ lymphocyte subpopulations.Results At baseline CD28 was expressed at a higher level on T lymphocytes from allergic patients than from control subjects (P 〈 0.04), and in particular on the CD8 subset (P 〈 0.01), reflecting a decrease in the suppressive CD8+CD28– subpopulation. No changes were found in the percentages of total CD28+ T cells, CD4+ CD28+ or CD8+CD28+ cells at the different time points after the initiation of immunotherapy.Conclusion These results suggest that the CD28 pathway is probably involved in the development of allergic reactions, but at least at the phenotypic level, CD28 expression remained unchanged after rush venom immunotherapy.

Notes: Eosinophils, mast cells and T lymphocytes are important cells in the allergic inflammatory process. These cells produce and are regulated by cytokines such as interleukin-3 (IL-3), interleukin-5 (IL-5) and granulocyte macrophage-colony stimulating factor (GM-CSF). We initiated this study to evaluate pathological abnormalities and to detect IL-5 in the duodenal mucosa from patients with food allergy.〈section xml:id="abs1-2"〉〈title type="main"〉MethodsEndoscopy duodenal biopsy specimens were obtained from seven food-allergic patients, six atopic healthy controls and six nonatopic healthy controls. IL-5 protein was evaluated by immunohistochemistry. Electron microscopy as well as double immunofluorescent staining were used to identify the labelled cells and to localize IL-5. IL-5 mRNA expression was evaluated by qualitative polymerase chain reaction.〈section xml:id="abs1-3"〉〈title type="main"〉ResultsA significantly increased number of lymphocytes, mast cells and eosinophils was detected in the lamina propria in food-allergic patients and, in lower number, in atopic controls. Immunostaining for IL-5 was markedly positive in food-allergic patients, slightly increased in atopic controls and negative in nonatopic controls. Ultrastructurally, in food-allergic patients and in atopic controls, IL-5 was localized in eosinophil granules, in the matrix of intact granules and at the periphery of altered granules. Double immunofluorescent staining was performed in food-allergic patients and showed that 86.7% of IL-5+ cells were eosinophils, and that IL-5 was expressed by 24% of eosinophils. IL-5 mRNA was expressed in food-allergic patients but was not detected in atopic and nonatopic controls.〈section xml:id="abs1-4"〉〈title type="main"〉ConclusionActivated eosinophils are involved in gut atopic reactions occurring in food allergy and are probably in part upregulated by their own local production of IL-5.

Notes: Background:  To improve asthma control, the management of rhinosinusitis often leads the physician to perform sinonasal imaging and/or nasal endoscopy, but their respective contributions are still insufficiently understood.Objective:  To evaluate the potential contribution of a symptoms questionnaire, sinus radiography (SR) and computed tomography (CT) scan to the diagnosis of nasal diseases in asthmatic patients when compared with ENT examination.Methods:  A total of 124 patients completed a questionnaire on nasal symptoms administered by the chest physician. Then, they underwent ENT examination. On the same day, SR and CT scans were performed independently.Results:  Patients (80.3%) had nasal symptoms during the month preceding the consultation. The ENT examination was normal in 8.1% (n = 10) and revealed rhinitis in 57.3% (n = 71), rhinosinusitis in 14.5% (n = 18) and nasal polyposis in 20.2% (n = 25). For rhinitis, the negative predictive value of bilateral nasal obstruction was 87.8%. Both SR and CT had low sensitivity and specificity. For rhinosinusitis, the negative predictive value of nasal symptoms varied from 85.4 to 95.2%. Sinus CT was at least as accurate as SR for the diagnosis of rhinosinusitis. In a multivariate analysis, only the CT scan (score ≥12) appeared to be significantly associated with the diagnosis of nasal polyposis.Conclusion:  In asthmatic patients, physicians need to enquire systematically about the existence of nasal symptoms by using this simple questionnaire which is sensitive for rhinitis, and has good negative predictive value for excluding rhinosinusitis and nasal polyposis.

Notes: Background: Patients with food allergy (FA) have been recently shown to develop bronchial hyperresponsiveness (BHR), despite the absence of any concomitant asthmatic manifestation. In order to explain this observation, we sought to examine the presence of a bronchial inflammation in induced sputum of nonasthmatic patients with FA. Methods: Twelve nonasthmatic patients with FA (urticaria, digestive symptoms, anaphylaxis) were included in the study. Results were compared to these obtained from eight asthmatic patients without food allergy and eight healthy controls. Diagnosis of FA was based on double-blind placebo-controlled challenge. Sputum cells and fluid-phase eosinophil cationic protein (ECP), myeloperoxidase (MPO) and interleukin-8 (IL-8) were measured in induced sputum. BHR was evaluated using methacholine inhalation. Results: Sputum from asthmatics, in comparison with the sputum of healthy subjects and patients with FA contained a higher proportion of eosinophils and higher levels of ECP (〈 0.001). In marked contrast, patients with FA exhibited an increased proportion of neutrophils and IL-8 in comparison with asthmatics and controls (P 〈 0.05 for neutrophils and P 〈 0.001 for IL-8). There was a significant correlation between sputum neutrophils and IL-8 (r = 0.68, P 〈 0.001). MPO levels were not different between the groups. There was a trend toward higher levels of IL-8 and ECP in food allergic patients with BHR in comparison with patients with FA without BHR. Conclusion: Our results demonstrate that a subclinical neutrophil airway inflammation is present in patients with food allergy free of clinical respiratory symptoms and that IL-8 may be an important mediator of this neutrophilia.

Notes: Background: Nasal polyposis (NP), a chronic inflammatory disease of the paranasal sinus mucosa, is frequently associated with asthma. Previous reports showed that surgical treatment for nasal polyps may influence asthma evolution. We hypothesized that sinus surgery may alter the cytokine network in nasal secretions. Methods: We evaluated the characteristics (cells and mediators) of nasal lavages in nine patients with untreated NP (group A), 17 patients treated with topical steroids (group B), 21 patients treated by nasal surgery – endonasal ethmoidectomy – associated with topical steroids (group C), and 12 healthy subjects (controls). Results: Percentages of both eosinophils and neutrophils were higher in NP patients than in controls. Percentages of eosinophils and interleukin-5 (IL-5) level were higher in group A than in group C and controls. There was a positive correlation between IL-5 and eosinophils. In marked contrast, IL-8, IL-10, and IL-1β levels were significantly higher in group C than in groups A and B and controls; TNF-α concentration was significantly lower in group C than in groups A and B and controls; and there was a negative correlation between IL-10 and TNF-α. The percentage of eosinophils was higher in asthmatic patients with NP than in nonasthmatic patients. In addition, in group C, asthmatic patients also had a significantly higher level of IL-10 than nonasthmatic patients. Conclusions: Our study demonstrates that percentages of eosinophils and neutrophils, and IL-5 level were increased in nasal secretions from untreated patients with NP. Topical steroid treatment is associated with a decrease of inflammatory cells and mediators. In marked contrast, nasal surgery is associated with marked changes, in cytokine profile in nasal secretions, that are clearly different from those of controls and topical steroid-treated NP patients.