Lung and blood Th1 and Th17 responses against mycobacterial antigens in patients with pulmonary sarcoidosis. (114.9)

• Published in: JOURNAL OF IMMUNOLOGY Vol. 186; no. 1_Supplement; pp. 114 - 114.9
• Main Authors: Ostadkarampour, Mahyar, Eklund, Anders, Moller, David, Grunewald, Johan, Wahlström, Jan
• Format: Journal Article Conference Proceeding
• Language: English
• Published: 01.04.2011
• Subjects: Medicin och hälsovetenskap
• DOI: 10.4049/jimmunol.186.Supp.114.9
• ISSN: 0022-1767

Abstract Sarcoidosis is an inflammatory disorder characterized by granulomas most commonly affecting the lungs. The presence of mycobacterial antigens, and recently a specific protein, M. tuberculosis catalase-peroxidase (mKatG), in sarcoidosis tissue has been reported. Th1 cell responses against mKatG have been observed in sarcoidosis lung and peripheral blood cells. IL-17 and IFNγ were evaluated by ELISPOT after stimulation of bronchoalveolar lavage (BAL) fluid and peripheral blood cells with mKatG and M. tuberculosis PPD proteins. Two groups of sarcoidosis patients were compared: HLA-DR3 positive (good prognosis) versus HLA-DR3 negative (bad prognosis). We also did dual-color Fluorospot assay and immunohistochemistry for further characterization. Both mKatG and PPD stimulation of BAL cells resulted in higher frequencies of cells producing IFNγ compared to IL-17. We did not detect any significant difference between BAL and blood regarding IL-17 secretion after stimulation with mKatG, while significantly more BAL cells produced IFNγ in comparison to blood after stimulation with mKatG (p<0.05). Preliminary data do not indicate any difference between patient subgroups regarding IL-17 production. The existence of IL-17+ cells in the granulomas also supports the role of IL-17 in sarcoidosis. The observed Th17 responses against mycobacterial antigens could contribute to the inflammation in sarcoidosis, although they generally occur at lower frequencies than corresponding Th1 responses.