Th1 and th2 cytokine profiles in malignant pleural effusion

ABSTRACT

The alteration of Thl and Th2 cytokine levels is the subject of controversy in pleural effusions caused by malignancy, a situation that favors a Th2 immune response. To examine the different levels of IL-4 and IL-10 [Th2 cytokines], and IL-2 and interferon-y [IFN-gamma] [Thl cytokines] in malignant and non-malignant pleural effusions. The cytokine levels in pleural fluid of 62 patients with malignant pleural effusion [44 with lung cancer and 18 with extrathoracic tumors], 8 with tuberculous and 8 with congestive heart failure pleural effusion were analysed using enzyme-linked immunosorbent assays. IL-2 was below the detectable concentration of the assay. A significant decrease in IFN-gamma level was observed in malignant but not in congestive heart failure cases compared to tuberculous cases. IL-10 levels were higher in malignant and tuberculous pleural effusions than in congestive heart failure pleural effusions, however, this difference did not reach the significant level. IL-4 levels were also increased non-significantly in lung cancer pleural effusions compared to the other groups. Our results show a wide variation in IL-4, IL-10, and IFN-gamma levels in malignant pleural effusions, a pattern which was not convincing enough to differentiate the cause of effusion