@article {SchuppP3786, author = {Jonas Schupp and Benedikt J{\"a}ger and Joachim M{\"u}ller-Quernheim and Antje Prasse}, title = {Th17 cell paradox in sarcoidosis}, volume = {42}, number = {Suppl 57}, elocation-id = {P3786}, year = {2013}, publisher = {European Respiratory Society}, abstract = {Background:Sarcoidosis is a systemic granulomatous disorder with a still unknown cause. Muliple evidence shows that saroidosis is associated with a strong Th1 immune response. Up to date, only few studies evaluated the potential role of Th17 cells. While immunohistochemistry data showed IL-17 upregulation in sarcoid granuloma, IL-17 overproduction by BAL cells has not been demonstrated.Objectives:To compare the gene expression profiles of BAL cells from sarcoid patients with healthy volunteers focused on the Th17 signature.Methods:50 patients with sarcoidosis and 20 healthy volunteers underwent bronchoscopy with bronchoalveolar lavage. BAL cells were isolated using a standard protocol. Gene expression was quantified by using Human Gene 1.0 ST Arrays (Affymetrix, Santa Clara, USA), as analysis software we used the BRB tool developed by Richard Simon.Results:Gene expression of BAL cells of patients with sarcoidosis differed in \>10000 genes (with a FDR \< 0.01) compared to BAL cells of healthy volunteers. Multiple genes, specific for Th17 cells (IL23R, RORC, CCR6, DPP4, CXCR3, IL1R1, IL12RB1, CD4, STAT3) were up regulated, but effector cytokines were paradoxically downregulated (IL17A, IL17F, IL21, IL22).Conclusion:Gene expression of BAL cells from sarcoid patients differs highly compared to healthy volunteers. Th17 cells seem to be elevated, but functionally repressed. Confirmation via flow cytometry, ELISA and immunohistochemistry are in progress and will be available at the ERS conference 2013.}, issn = {0903-1936}, URL = {https://erj.ersjournals.com/content/42/Suppl_57/P3786}, eprint = {https://erj.ersjournals.com/content/42/Suppl_57/P3786.full.pdf}, journal = {European Respiratory Journal} }