Expression analysis of extracellular microRNA in bronchoalveolar lavage fluid from patients with pulmonary sarcoidosis.

BACKGROUND AND OBJECTIVE: MicroRNA (miRNA) are transcriptional regulators implicated in pulmonary sarcoidosis and packaged in extracellular vesicles (EV) during cellular communication. We characterized EV and investigated miRNA expression in bronchoalveolar lavage (BAL) fluid from sarcoidosis patients. METHODS: EV were characterized for size(s) using dynamic light scattering and transmission electron microscopy (TEM) analysis and protein markers by immunoblotting. Twelve extracellular and 5 cellular miRNA were investigated in BAL from 16 chest X-ray stage-I (CXR-I) and 17 CXR stage-II (CXR-II) sarcoidosis patients. Associations between miRNA and disease characteristics (extrapulmonary involvement, pulmonary function and BAL cell profile) were statistically analysed. RESULTS: BAL from sarcoidosis patients contained exosomes and microvesicles (MV) as EV. In these EV, expression of miR-146a (P = 0.007), miR-150 (P = 0.003) and BAL cellular miR-21 (P = 0.01) was increased in CXR-II compared with CXR-I. Other detected EV (miR-21 and miR-26a) and cellular (miR-31, miR-129-3p, miR-146a and miR-452) miRNA were not differentially expressed. The investigated miRNA did not reflect extrapulmonary involvement, but EV miR-146a and miR-150 were negatively correlated with pulmonary function (miR-146a with vital capacity (VC; Spearman's correlation coefficient (rs ), P = -0.657, 0.007), percent predicted forced expiratory volume in 1 s (FEV1 ; -0.662, 0.006) and FEV1 /forced vital capacity (FVC) ratio (-0.649, 0.008); miR-150 correlated negatively with VC (-0.584, 0.019) and FEV1 /FVC ratio (-0.746, 0.001) in CXR-II cases). CONCLUSION: Our data provide evidence that exosomes and microvesicles as extracellular vesicles are present in the bronchoalveolar space of sarcoidosis patients and they differentially express EV miRNA (miR-146a and miR-150), the expression of which correlates negatively with pulmonary function indices. The significance of these findings for disease pathophysiology and clinical course require further investigation.

The Serum Expression of Selected miRNAs in Pulmonary Sarcoidosis with/without Löfgren's Syndrome.

Purpose. Pulmonary sarcoidosis is associated with dysregulated expression of intracellular miRNAs. There is however only little information on extracellular miRNAs and their association with the disease course in sarcoidosis. We therefore assessed serum miRNAs in sarcoidosis classified according to the presence of Löfgren's syndrome (LS) as a hallmark of good prognosis in contrast to more advanced disease course. Methods. RT-PCR was used to assess 35 miRNAs in 13 healthy controls and 24 sarcoidosis patients (12 with X-ray (CXR) stage ≤ 1 and LS and 12 with insidious onset and CXR stage ≥ 3). Results. Compared to controls, we consistently observed dysregulated expressions of miR-146, miR-16, miR-425-5p, and miR-93-5p in both sarcoidosis groups irrespective of disease course. Specifically, patients without LS had dysregulated expressions of miR-150-5p, miR-1, and miR-212 compared to controls. Patients with LS had dysregulated expressions of miR-21-5p and miR-340-5p compared to controls. Bioinformatics predicted consistently "Pathways in cancer" to be modulated by both altered profiles in patients with/without LS. Three miRNAs (miR-21-5p, miR-340-5p, and miR-212-3p) differed between our patients with LS and those without LS; their cumulative effect may modulate "TGF-ß signalling pathway." Conclusions. Further study should focus on possible applications of serum miRNAs for diagnostics follow-up and for prognosis.

The Expression of T Cell FOXP3 and T-Bet Is Upregulated in Severe but Not Euthyroid Hashimoto's Thyroiditis.

Hashimoto's thyroiditis (HT) is an organ-specific autoimmune disorder characterized by progressive thyroid failure. Th1 and Treg subset of CD4(+) cells have been implicated in the pathogenesis; however, less is known about their respective roles across the spectrum of HT clinical presentations. To shed more light on CD4(+) subsets role in HT, we investigated the mRNA expression levels of several Th1/Treg-associated transcription factors (T-bet/ETS1, HIF1α/BLIMP1/FOXP3) in peripheral blood T cells of 10 hypothyroid, untreated HT patients, 10 hypothyroid patients undergoing hormone replacement therapy, 12 euthyroid HT subjects, and 11 healthy controls by the qRT-PCR. Compared to euthyroid HT patients and controls, both hypothyroid (2.34-fold difference versus controls, P < 0.01) and thyroxine-supplemented patients (2.5-fold, P < 0.001) showed an increased FOXP3 mRNA expression in T cells. Similarly, mRNA expression levels of T-bet were upregulated in severely affected but not in euthyroid HT subjects (2.37-fold and 3.2-fold, hypothyroid and thyroxine-supplemented HT patients versus controls, resp., P < 0.01). By contrast, no differences in mRNA expression levels of ETS1, BLIMP1, and HIF1α were observed across the study groups. In summary, severe but not euthyroid HT was associated with robust upregulation of T-bet and FOXP3 mRNA in peripheral T cells, independent of the thyroid hormone status but proportional to disease activity.

Comparison of lymphocyte immune phenotypes in bronchoalveolar lavage of non-smoking patients with sarcoidosis and other interstitial lung diseases.

BACKGROUND: Bronchoalveolar lavage (BAL) as complementary method is still used as ancillary tool in diagnosis of interstitial lung diseases. Tobacco smoking has been described to affect the BAL lavage cellular profile. To our knowledge, only few reports have so far investigated CD3+CD4+ and CD3+CD8+ lymphocyte subsets in non-smoking sarcoidosis patients additionally stratified according to CXR stage, and compared them to other non-smoking patients with interstitial lung diseases (ILDs). METHODS: We compared lymphocytes immune phenotypes, subsets, with CD3+, CD3+CD4+ and CD3+CD8+ cell markers, in the non-smoking subjects (n=297) including the patients with pulmonary sarcoidosis (S), idiopathic pulmonary fibrosis (IPF) (n=22), hypersensitivity pneumonitis (HP) (n=15), other interstitial idiopathic pneumonias (OIIPs) (n=39). According to prognosis, the patients with S were divided into four groups: 18 patients with Löfgren's syndrome (LS) in chest X-ray (CXR) ≤1 stage, 64 patients without LS in CXR ≤1 stage, 113 patients in CXR 2 stage and 26 patients with advanced CXR ≥3 stage. RESULTS: After the use of false discovery rate (FDR) correction, relative numbers (%) of CD3+, CD3+CD4+, CD3+CD8+ and CD3+CD4/CD3+CD8 ratio showed the most significant differences between the non-smokers with S (both with/without LS) and the non-smokers with other ILDs (IPF, OIIPs, HP). These lymphocytes subsets were further altered in the non-smokers with CXR stage 2 compared to the non-smokers with other ILDs (IPF, OIIPs, HP). We did not observe any differences in these lymphocyte subsets and CD3+CD4+/CD3+CD8+ ratio between the non-smokers with advanced sarcoidosis stage (CXR ≥3) and the non-smokers with IPF. CONCLUSIONS: Our data on the non-smokers confirmed the presence of the typical BAL cellular profile in sarcoidosis. The BAL cellular profile was helpful namely for differentiation of less advanced sarcoidosis. Its definite diagnostic utility should be the subject of further clinical studies with large numbers of the well characterized patients taking into consideration other clinical factors influencing BAL cellular profile, such as smoking or treatment.

Expression Profile of Six RNA-Binding Proteins in Pulmonary Sarcoidosis.

BACKGROUND: Sarcoidosis is characterised by up-regulation of cytokines and chemokine ligands/receptors and proteolytic enzymes. This pro-inflammatory profile is regulated post-transcriptionally by RNA-binding proteins (RBPs). We investigated in vivo expression of six RBPs (AUF1, HuR, NCL, TIA, TIAR, PCBP2) and two inhibitors of proteolytic enzymes (RECK, PTEN) in pulmonary sarcoidosis and compared it to the expression in four control groups of healthy individuals and patients with other respiratory diseases: chronic obstructive pulmonary disease (COPD), asthma and idiopathic interstitial pneumonias (IIPs). METHODS: RT-PCR was used to quantify the mRNAs in bronchoalveolar (BA) cells obtained from 50 sarcoidosis patients, 23 healthy controls, 30 COPD, 19 asthmatic and 19 IIPs patients. Flow cytometry was used to assess intracellular protein expression of AUF1 and HuR in peripheral blood T lymphocytes (PBTLs) obtained from 9 sarcoidosis patients and 6 healthy controls. RESULTS: Taking the stringent conditions for multiple comparisons into consideration, we consistently observed in the primary analysis including all patients regardless of smoking status as well as in the subsequent sub-analysis limited for never smokers that the BA mRNA expression of AUF1 (p<0.001), TIA (p<0.001), NCL (p<0.01) and RECK (p<0.05) was decreased in sarcoidosis compared to healthy controls. TIA mRNA was also decreased in sarcoidosis compared to both obstructive pulmonary diseases (COPD and asthma; p<0.001) but not compared to IIPs. There were several positive correlations between RECK mRNA and RBP mRNAs in BA cells. Also sarcoidosis CD3+, CD4+ and CD8+ PBTLs displayed lower mean fluorescence intensity of AUF1 (p≤0.02) and HuR (p≤0.03) proteins than control healthy PBTLs. CONCLUSION: mRNA expressions of three RBPs (AUF1, TIA and NCL) and their potential target mRNA encoding RECK in BA cells and additionally protein expression of AUF1 and HuR in PBTLs were down-regulated in our sarcoidosis patients compared to healthy individuals. Its significance, e.g. for stability of mRNAs encoding pro-inflammatory factors, should be further explored in sarcoidosis.