RESUMO
Human bronchial asthma is characterized by airway hyper responsiveness [AHR], eosinophilic airway inflammation, mucous hypersecretion and high serum level of IgE. AHR and mucus over secretion are often linked to asthma symptoms and morbidity. Although the mechanisms underlying these features are complex, it is widely accepted that TH2 cells which produce a limited repertoire of cytokines are responsible for inducing these characteristic features of bronchial asthma. The aim of this study is to investigate the levels of serum soluble fractalkine [CX3C] and interleukin IL-18 in a group of patients with bronchial asthma. This study was conducted on 55 subjects who were divided into three groups, 20 patients with bronchial asthma who were not receiving corticosteroidal treatment, 20 patients with bronchial asthma and were receiving inhaled steroids such as beclomethasone diproprionate and 15 normal subjects as a control group. The patients were selected from either inpatients in Al-Zahraa University Hospital internal medicine or outpatients from the internal medicine Clinic. Five milliliters of peripheral venous blood were collected and divided into two tubes; one of them contained EDTA to be tested for complete and differential blood count. From the other tube, serum is separated and stored at - 80?C until serum levels of soluble fractalkine, IL-18 and IgE are estimated using commercially available ELISA kits. In the present study serum soluble fractalkine [3535.3 +/- 3697.3] pg/ml, IL-18 [1431.5 +/- 716.58] pg/ml and serum IgE[257.27 +/- 73.300] IU/ml levels were higher in asthmatic patients than healthy controls which were [72.000 +/- 7.270] pg/ml, [352.86 +/- 127.29] pg/ml and [63.573 +/- 19.719] IU/ml respectively with statistical significant difference between them. By comparing these parameters between group1 and group 2, it was found that serum soluble fractalkine level was higher in group 2 [6700.0 +/- 2054.8] pg/ml than group 1 [170.50 +/- 57.260] pg/ml and the difference between them was highly significant. On the other hand IL-18 [1362.8 +/- 654.03] pg/ml was slightly lower in group 2 than group 1[1500.3 +/- 785.05] pg/ml and the statistical difference between them were not significant. Serum IgE level was lower in group 2 [231.75 +/- 80.733] IU/ml than group 1[282.79 +/- 56.030] IU/ml with statistically significant difference between them. In conclusion, both serum IL-18 and soluble fractalkine were elevated with allergic bronchial asthma independently of serum IgE level. Furthermore, corticosteroid inhalation has no effect on IL-18. On the other hand, it decreases the level of serum IgE but also increases the level of serum soluble fractalkine