IL-4 and IL-5 mRNA Expression In The Sputum and Bronchoalveolar Lavage Of Patients With Bronchial Asthma. A Comparative Study.

1Hala A.F.Ismaiil, 2Hoda M. Bahr, 3Eman A.Mashhour, 3Enas Arafa, 2Amgad A. Farahat, 4Heba A.Mashhour, 5Engi Abdel Wahab

Departments of 1Microbiology, 2Chest, 3Clinical Pathology, 4Pathology and 5Internal Medicine, Faculty of Medicine, Tanta University, Egypt.

Cytokines play an integral role in the chronic inflammation of the airways in asthma. The local production of Th2-type cytokines is thought to orchestrate the ongoing eosinophilic inflammation and contribute to the pathophysiologic features of atopic asthma. to determine whether induced sputum could be substituted for bronchoalveolar lavage (BAL) to monitor cytokine expression in asthmatic airways, Intreleukin-4 (IL-4) and Intreleukin-5 (IL-5) expression in sputum and BAL of 20 atopic and 20 non atopic asthmatic subjects as well as 10 non asthmatic controls were compared. In the atopic asthmatic group IL-4 mRNA was detected in the sputum of 10(50%) and in the BAL of 18(90%). Meanwhile, mRNA encoding the IL-5 was detected in the sputum of 6(30%) and BAL of 18 (90%) cases of the same group. In the non atopic asthmatics, expression of`IL-4 was detected in the sputum of 6 (30%) and BAL of 16 (80%) subjects whereas IL-5 mRNA was expressed in the sputum of 8(40%) and BAL of 18 (90%) cases. In contrast, the control group showed expression of IL-4 mRNA in the sputum and BAL of 1 and 3 subjects respectively and IL-5mRNA expression in the sputum and BAL of 2 and 3 subjects respectively. It is concluded that asthma is associated with local expression of IL-4 and IL-5 and that induced sputum can be used to monitor the expression of cytokine mRNA but BAL is still preferable.