Increased levels of Treg cells in bronchoalveolar lavage fluid and induced sputum of patients with active pulmonary sarcoidosis

Abstract

ObjectiveIt has recently been described that circulatory and BAL regulatory T-cells (Tregs), defined as CD4+CD25highCD127low are increased in patients with active sarcoidosis compared with other interstitial lung diseases.Materials and methodsWe studied prospectively 17 patients (10 women, 7 men) of median age 39 years (range 27-65) with active granulomatous lung diseases (GLD) (10 patients with sarcoidosis (BBS), and 7 with hypersensitivity pneumonitis (HP), and 9 healthy controls. Bronchoalveolar lavage fluid (BAL) and induced sputum Treg counts, CD4+, CD8+, CD25+ cells were quantified by flow cytometry. Disease activity was measured by ACE serum level. Pulmonary function tests were performed using an Elite DL Medgraphics body box.ResultsWe found Treg cells count significantly elevated in induced sputum from active GLD (38.3% vs. 7.1% and 5.3% in BBS, HP, and control, respectively). A significantly higher percentage of Treg cells characterized BAL cells from HP patients (2.27%; 9.5%; 2.1%, in BBS, HP and control, respectively). There was a strong correlation with ACE serum level and Treg cell count in BAL fluid of BBS patients, with no such correlation within HP patient group, nor Treg cell count and pulmonary function tests.ConclusionsOur data suggest a potential role of CD4+CD25 high CD127 low induced sputum and BAL lymphocytes from patients with active granulomatous lung diseases and hypersensitivity pneumonitis. An increased number of Treg cells in active GLD may be involved in immune regulation in active granulomatous lung diseases. The results indicate that analysis of these cells could be useful as markers of disease activity in granulomatous lung diseases.

Reversal of Global CD4+ Subset Dysfunction Is Associated with Spontaneous Clinical Resolution of Pulmonary Sarcoidosis

“…The key function of Tregs is to suppress T cell activation which can be measured by both T cell cytokine production and proliferation. Consistent with prior reports (6,18–20), we observed an increase in Tregs peripherally (Figure 3A). To investigate if Tregs contributed to the reduced cytokine production, we depleted Tregs from the CD4+ T cells by flow sorting the CD4+CD45RO+CD25 hi cells from total CD4+ T cells.…”

Inflammatory markers and pulmonary granuloma infiltration in sarcoidosis

“…The inflammatory response in sarcoidosis is characterized by an increase in several inflammatory mediators such as interleukin (IL)‐10, IL‐12 and tumour necrosis factor (TNF)α . Chitotriosidase (CTO) is of particular interest as it is a major defence enzyme against fungi .…”

Increased frequencies of pulmonary regulatory T-cells in latentMycobacterium tuberculosisinfection

“…High frequencies of Treg cells are also found in the BAL and blood of patients with other granulomatous lung diseases, such as sarcoidosis and Churg-Strauss syndrome, where they also correlate with disease activity [37][38][39]. In TB, the numbers of circulating Treg cells decrease after resection of pulmonary cavities [36].…”