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High-mobility group box 1 (HMGB1), a non-histone nuclear protein, has been implicated in cardiovascular diseases. Dilated cardiomyopathy (DCM), one of the leading causes of heart failure, is often caused by coxsackievirus B3-triggered myocarditis and promoted by the post-infectious autoimmune process. Th17 cells, a novel CD4 1 T subset, may be important in the pathogenesis of autoimmune myocarditis. In the present study, we attempted to block HMGB1 function with a monoclonal antibody specific for HMGB1 B box and investigated the effects of the blockade on Th17 cells and experimental autoimmune myocarditis (EAM). After induction of EAM, HMGB1 protein levels were significantly elevated both in the heart and blood. Administration of an anti-HMGB1 B box mAb attenuated cardiac pathological changes and reduced the number of infiltrating inflammatory cells in the heart during EAM. These protective effects of HMGB1 blockade correlated with a reduced number of Th17 cells in local tissues and lower levels of IL-17 in the serum. Furthermore, in vitro, studies demonstrated that HMGB1 promoted Th17-cell expansion. Therefore, we speculate that HMGB1 blockade ameliorates cardiac pathological changes in EAM by suppressing Th17 cells.Key words: Dilated cardiomyopathy . Experimental myocarditis . HMGB1 . Th17 cells IntroductionHigh-mobility group box 1 (HMGB1), a non-histone nuclear protein, has been functionally characterized as an alarmin or damage-associated molecular pattern (DAMP) [1,2]. It is constitutively expressed in quiescent cells and stored in the nucleus [3]. HMGB1 is one of the most evolutionarily conserved proteins in eukaryotes, with 100% identity between mice and rats, and 99% identity between rodents and humans [3].HMGB1 has been shown to be involved in both infectious and non-infectious inflammatory disease [2,4]. HMGB1 is released into the extracellular milieu during cell apoptosis/death [5], and by macrophages and monocytes in response to cellular stress or injury [6]. HMGB1 binds to the endogenous receptor for advanced glycation endproducts [7], exogenous toll-like receptor 2/4/9 (TLR2/4/9) [8,9], and CD24/Siglec-10 [10], and induces the expression of proinammatory cytokines, chemokines, and adhesion molecules [3,6]. Although, HMGB1 was initially 3586thought to be a late mediator of sepsis, recent data also indicated that HMGB1 is associated with many other pathological conditions, such as autoimmune disease [11], cancer [12][13][14], trauma, ischemia-reperfusion injury [15,16], tissue repair and regeneration [17,18], and cardiovascular diseases [19]. Furthermore, HMGB1 has restorative effects on CD4 1 T-helper cell modulation [20].Dilated cardiomyopathy (DCM) is one of the leading causes of severe heart failure and the most common indication for heart transplantation. DCM is often caused by coxsackievirus B3-triggered myocarditis [21]. Experimental autoimmune myocarditis (EAM) is a mouse model of postinfectious myocarditis, characterized by inflammatory infiltration of the myocardium and cardiac myocyte ne...

Expression of insulin-like growth factor II in two human hepatocellular carcinoma cell lines and in hepatitis B, cirrhosis and hepatocellular carcinoma in 419 cases were investigated, and its relationship with the expression of hepatitis B virus X gene was studied by means of immunohistochemical and electron microscopic techniques. The results demonstrated that hepatocellular carcinoma cells (SMMC 7721 and QGY 7703) in culture could express insulin-like growth factor II. Expression seemed to be regulated by cell density, which was suggested as the molecular basis of the contact inhibition of cell proliferation. In tissue sections, cells with high expression of insulin-like growth factor II were observed not only in hepatocellular carcinoma (93%) but also in 95% of the pericancerous liver tissues, 72% of cirrhotic livers, 64% of chronic active hepatitis and 37% of chronic persistent hepatitis. In most cases of hepatocellular carcinoma, insulin-like growth factor II was localized in the cytoplasm of the cancer cells. In the benign liver disorders, four types of cells that highly expressed insulin-like growth factor II were observed: (a) a kind of small liver cell we named the small polygonal liver cell; (b) multinuclear giant hepatocytes; (c) hepatocytes in most of hyperplastic and neoplastic nodules, small hepatocyte nodules and some of regenerative nodules; and (d) some proliferating ductular cells. Even more interestingly, insulin-like growth factor II expression was shown to be closely related to the expression of hepatitis B virus X gene product. We suggest that the activation of insulin-like growth factor II gene and its overexpression may be a crucial step in the processes of hepatitis B virus-associated hepatocarcinogenesis and that the X gene product may activate the insulin-like growth factor II gene through a transactivation mechanism. In addition, we studied the characteristics of small polygonal liver cells, and the roles they may play in the regeneration and carcinogenesis of hepatitis B virus-infected liver are discussed.

Rheumatoid arthritis(RA) is a common autoimmune disease associated with Th17 cells, but what about the effect of high-mobility group box chromosomal protein 1 (HMGB1) and the relationship between Th17-associated factors and HMGB1 in RA remains unknown. In the present study, we investigated the mRNA levels of HMGB1, RORγt, and IL-17 in peripheral blood mononuclear cells (PBMCs) from patients with rheumatoid arthritis by quantitative real-time PCR (RT-qPCR), and the concentrations of HMGB1, IL-17, and IL-23 in plasma were detected by ELISA. And then, the effect of HMGB1 on Th17 cells differentiation was analyzed in vitro. Our clinical studies showed that the mRNAs of HMGB1, RORγt, and IL-17 in patients were higher than that in health control (P < 0.05), especially in active RA patients (P < 0.05). The plasma HMGB1, IL-17, and IL-23 in RA patients were also higher than that in health control (P < 0.05); there was a positive correlation between the expression levels of HMGB1 and the amount of CRP, ERS, and RF in plasma. In vitro, the IL-17-produced CD4+T cells were increased with 100 ng/mL rHMGB1 for 12h, which indicated that the increased HMGB1 might contribute to Th17 cells activation in RA patients.

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