IRF7 gene expression profile and methylation of its promoter region in patients with systemic sclerosis.

OBJECTIVE: The aim of the current study was to evaluate if methylation status of CpG sites of interferon regulatory factor 7 (IRF7) promoter in peripheral blood mononuclear cells (PBMCs) of systemic sclerosis (SSc) patients is involved in pathogenesis of the disease. METHODS: PBMCs were isolated from whole blood of 50 SSc patients and 30 controls. After the extraction of total RNA and DNA contents from PBMCs, complementary DNA (cDNA) was synthesized. Afterwards, quantitative analysis of IRF7 messenger RNA (mRNA) was conducted by real-time polymerase chain reaction (PCR). To evaluate the methylation status of the promoter region of IRF7 gene, PCR products of bisulfite-treated DNA from SSc patients and controls were sequenced. RESULTS: The mRNA expression of IRF7 in PBMCs from patients compared with controls was significantly upregulated. While limited cutaneous SSc patients expressed the mRNA of IRF7 higher than controls, the diffuse cutaneous SSc group did not demonstrate significantly increased expression in comparison to controls. Insignificant promoter hypomethylation of IRF7 was observed in SSc patients compared with the control group. However, CpG2 hypomethylation was significantly associated with increased SSc risk. Furthermore, overall promoter methylation and mRNA level of IRF7 were significantly correlated with each other. Nonetheless, none of them correlated with Rodnan score of SSc patients. There was significant difference in IRF7 mRNA expression between CpG8 methylated and unmethylated SSc patients. Moreover, the difference of methylation and expression was not significant between anti-nuclear antibody (ANA)-positive and ANA-negative SSc patients. CONCLUSIONS: It is suggested that hypomethylation of the IRF7 promoter might play a role in SSc pathogenesis, probably through promoting the IRF7 expression in PBMCs of patients with SSc.

[The laboratory detection of intra-cellular factors of anti-viral defense under community-acquired pneumonia in evaluation of effects of low-intensity microwave radiation].

The study was carried out to investigate intro-cellular concentration of factors of antiviral defense of cells of whole blood of re-convalescents of community-acquired pneumonia and healthy individuals under effect of low intensity SHF-radiation of whole blood in vitro with frequency of 1000 MGz. The technique of enzyme-linked immunosorbent assay was applied for analyzing lysates of mononuclears of whole blood exposed to impact of low intensity SHF-radiation with frequency of1000 MGz on concentration of mitochondrial antiviral signal protein MAVS, RIG-I-like receptor type III - helicase LGP2, RIG-I-like receptor - helicaseMDA5, trans-membrane protein 173 (Tmem 173), interferon-regulated factors (IRF) 3,7 and 8, sub-units p50 and p65 of nuclear factor of transcription NF-kB, phosphorylated on serine in position form 32 of inhibitor of nuclear factor of transcription (IkB-a) and also its total concentration. Besides, spontaneous production of interferon - a/ß by cells of whole blood was evaluated in cellular supernatant. The capacity of single 20 minutes of SHF-radiation effect to increase intracellular level of important regulative proteins, primarily MDA5, during the phase of convalescence of community-acquired pneumonia was established. Besides, radiation stimulates increasing of intracellular level of MAVS and Tmem173. The capacity of radiation was established to increase phosphorylation of inhibitor of nuclear factor NF-kB and level of components p50 and p65 of NF-kB. The capacity of SHF-radiation effecting production of interferon-ß by cells of hole blood is demonstrated. In healthy individuals, radiation contributes into decreasing of intercellular content of MAVS in more degree as compared with levels of MDA5 and Tmem173. At that, radiation of culture of cells of whole blood stimulates increasing of production of interferons.

Interleukin-6 and type I interferon-regulated genes and chemokines mark disease activity in dermatomyositis.

OBJECTIVE: Up-regulation of whole blood type I interferon (IFN)-driven transcripts and chemokines has been described in a number of autoimmune diseases. An IFN gene expression "signature" is a candidate biomarker in patients with dermatomyositis (DM). This study was performed to evaluate the capacity of IFN-dependent peripheral blood gene and chemokine signatures and levels of proinflammatory cytokines to serve as biomarkers for disease activity in adult and juvenile DM. METHODS: Peripheral blood samples and clinical data were obtained from 56 patients with adult or juvenile DM. The type I IFN gene signature in the whole blood of patients with DM was defined by determining the expression levels of 3 IFN-regulated genes (IFIT1, G1P2, and IRF7) using quantitative real-time reverse transcription-polymerase chain reaction. Multiplexed immunoassays were used to quantify the serum levels of 4 type I IFN-regulated chemokines (IFN-inducible T cell alpha chemoattractant, IFNgamma-inducible 10-kd protein, monocyte chemotactic protein 1 [MCP-1], and MCP-2) and the serum levels of other proinflammatory cytokines, including interleukin-6 (IL-6). RESULTS: DM disease activity correlated significantly with the type I IFN gene signature (r = 0.41, P = 0.007) and with the type I IFN chemokine signature (r = 0.61, P < 0.0001). Furthermore, the serum levels of IL-6 were significantly correlated with disease activity (r = 0.45, P = 0.001). In addition, correlations between the serum levels of IL-6 and both the type I IFN gene signature (r = 0.47, P < 0.01) and the type I IFN chemokine signature (r = 0.71, P < 0.0001) were detected in patients with DM. CONCLUSION: These results suggest that serum IL-6 production and the type I IFN gene signature are candidate biomarkers for disease activity in adult and juvenile DM. Coregulation of the expression of IFN-driven chemokines and IL-6 suggests a novel pathogenic linkage in DM.

Expression of interferon regulatory factor 1, 3, and 7 in primary Sjögren syndrome.

OBJECTIVE: The aim was to investigate the level of interferon regulatory factor (IRF) 1, 3, and 7 in peripheral blood cells from patients with primary Sjogren syndrome (pSS) and to determine whether and where IRF1 exists in the parotid glands of pSS. METHODS: Peripheral blood cells and parotid gland biopsy specimens from patients with pSS were studied. The IRF1, IRF3, and IRF7 gene mRNA levels in peripheral blood cells were calculated by using real-time PCR. The IRF1-positive cells in the parotid glands with pSS were observed by using immunohistochemistry and immunofluorescence. Statistical analysis was performed by Student t test. RESULTS: Compared with 24 control samples, the IRF1 mRNA levels in peripheral blood cells of 37 cases with pSS were up-regulated (P < .05), but the IRF3 and IRF7 mRNA levels of pSS were not up-regulated (P > .05). Relative quantitative levels of IRF1 mRNA were 2.17-fold higher in pSS patients than control subjects. The IRF1-positive cells of the pSS group were localized in the epithelial islands, lymphocytes, and ductal epithelial cells of the parotid glands. In all control subjects, the IRF1-positive cells were localized only to the ductal epithelial cells of parotid glands as determined by immunohistochemical staining or immunofluorescence. The scores of IRF1-positive cells of pSS were significantly higher than that of control samples (P < .05). CONCLUSION: These findings indicate that IRF1 mRNA levels are up-regulated in the peripheral blood cells of pSS patients. Also, IRF1-positive cells exist in the epithelial islands, lymphocytes, and ductal epithelial cells of the parotid glands of individuals affected by pSS, but are limited to the ductal epithelial cells of healthy control subjects.