T cells subtypes in pleural effusion of tuberculous and non-tuberculous patients

<b>Background:</b> Tuberculous pleural effusion (TPE) is one of the most common forms of extrapulmonary tuberculosis. Patients with tuberculous or malignant pleural effusions (MPE) frequently have similar lymphocytic pleural fluid profile. <b>Objective:</b> We aimed to determine whether T helper (Th) subsets able to differentiates TPE from non-TPE patients. <b>Methods:</b> 30 patients with TPE, 30 patients with MPE, 14 patients with EMP and 14 patients with PPE were enrolled between Dec 2018-2019, Tehran-Iran. 3 ml fresh PE harvested and after staining with related Abs, the frequency of T cells phenotypes; CD4+IL-9+, CD4+IL-22+, CD+IL-17+ and CD4+CD25+FOXP3+T cells were determined by flowcytometry. <b>Results:</b> D4+CD25+FOXP3+ T cells were detected as important markers for TPE (P&lt;0.0001). There were a significant differences in of CD4+IL-9+ T cells in TPE in compared to non-TPE (P&lt;0.0001). But, the frequency of CD+IL-17+ and CD4+IL-22+ T cells had no significant difference between TPE and non-TPE patients (P=0.0906 and P=0.2188, respectively). <b>Conclusion:</b> The current data suggests that high frequency of CD4+CD25+FOXP3+ T cells may differentiates TPE from non-TPE and future studies with multicenter studies is needed for generalize this finding as a biomarkers.