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Shinji Shimoda

Publications and source records attributed to Shinji Shimoda.

At least 19 recordsLinked to original sources
PubMed2006

Adult T-cell leukemia development from a human T-cell leukemia virus type I carrier after a living-donor liver transplantation.

Adult T-cell leukemia (ATL) develops in a human T-cell leukemia virus type I (HTLV-I) carrier. The development of malignancy during immunosuppressive treatment following organ transplantation is one of the late fatal complications. We describe the development of three cases of ATL in eight HTLV-I carriers within 164 living-donor liver transplant recipients undergoing immunosuppressive treatment. All three cases were immunosuppressed with tacrolimus. Acute-type ATL was diagnosed at 6, 9, and 25 months after living-donor liver transplantation, based on increased numbers of CD4+25+ lymphocytes exhibiting "flower-like" nuclei, and the elevation of lactate dehydrogenase. Southern blot analysis demonstrated the clonal proliferation of ATL cells in peripheral blood. The ATL cells originated from the recipient, as demonstrated by fluorescence in situ hybridization analysis using sex chromosomal markers. Our observations suggest that immunosuppressive treatment for the prevention of graft rejection after living-donor liver transplantation may induce the development of ATL in an HTLV-I carrier.

Adult↗
PubMed2006

Purified human hematopoietic stem cells contribute to the generation of cardiomyocytes through cell fusion.

To obtain insights into the cardiomyogenic potential of hematopoietic tissue, we intravenously (i.v.) injected purified hematopoietic stem/progenitor cells into newborn recipients that may fully potentiate the developmental plasticity of stem cells. Transplantation of mouse bone marrow (BM) lineage antigen-negative (Lin-) cells resulted in the generation of the cells that displayed cardiomyocyte-specific antigenic profiles and contractile function when transplanted into syngeneic newborn recipients. To clarify the mechanism underlying the cardiomyogenic potential, green fluorescent protein (GFP)-labeled BM Lin-ScaI+ hematopoietic progenitors were transplanted into neonatal mice constitutively expressing cyan fluorescence protein (CFP). Lambda image acquisition and linear unmixing analysis using confocal microscopy successfully separated GFP and CFP, and revealed that donor GFP+ cardiomyocytes coexpressed host-derived CFP. We further reconstituted human hemopoietic- and immune systems in mice by injecting human cord blood (CB)-derived Lin-CD34+CD38- hematopoietic stem cells (HSCs) into neonatal T cell(-)B cell(-)NK cell- immune-deficient NOD/SCID/IL2rgamma(null) mice. Fluoroescence in situ hybridization analysis of recipient cardiac tissues demonstrated that human and murine chromosomes were colocalized in the same cardiomyocytes, indicating that cell fusion occurred between human hematopoietic progeny and mouse cardiomyocytes. These syngeneic- and xenogeneic neonatal transplantations provide compelling evidence that hematopoietic stem/progenitor cells contribute to the postnatal generation of cardiomyocytes through cell fusion, not through transdifferentiation.

Animals↗
PubMed2006

Interferon alpha plus ribavirin combination treatment of Japanese chronic hepatitis C patients with HCV genotype 2: a project of the Kyushu University Liver Disease Study Group.

AIM: To determine the efficacy of an interferon alpha and ribavirin combination treatment for Japanese patients infected with hepatitis C virus (HCV) of genotype 2, a multi-center study was retrospectively analyzed. METHODS: In total, 173 patients with HCV genotype 2 started to receive interferon-alpha subcutaneously thrice a week and 600-800 mg of ribavirin daily for 24 wk. RESULTS: The overall sustained virological response (SVR), defined as undetectable HCV RNA in serum, 24 wk after the end of treatment, was remarkably high by 84.4%, (146/173) by an intention-to-treat analysis. A significant difference in SVR was found between patients with and without the discontinuation of ribavirin (46.9% vs 92.9%), but no difference was found between those with and without a dose reduction of ribavirin. A significant difference in SVR was also found between patients with less than 16 wk and patients with 16 or more weeks of ribavirin treatment (34.8% vs 92.0%). CONCLUSION: The 24-wk interferon and ribavirin treatment is highly effective for Japanese patients with HCV genotype 2. The significant predictor of SVR is continuation of the ribavirin treatment for up to 16 weeks.

Adult↗
PubMed2006

Long-term lamivudine treatment for chronic hepatitis B in Japanese patients: a project of Kyushu University Liver Disease Study.

AIM: To determine the efficacy of long-term lamivudine treatment of a large number of Japanese patients with chronic hepatitis B. METHODS: In this retrospective, multi-center trial, 318 Japanese patients with chronic hepatitis B received 100 mg of lamivudine daily for up to 36 (median 21) mo. Virological response was a decline to a serum HBV DNA level less than 3.7 log copies/mL. Virological breakthrough was defined as the reappearance of a serum HBV DNA level to more than 10-fold the minimum during treatment. RESULTS: Lamivudine produced virological response in 86.8% of the 318 patients at 6 mo, in 80.2% of 252 patients at 12 mo, in 69.2% of 133 patients at 24 mo, and in 53.6% of 28 patients at 36 mo. Forward stepwise logistic regression analysis showed an HBV DNA level less than 6.8 log copies/mL (P<0.0001), HBeAg negativity (P<0.0001), a platelet count of 100 x 10(9)/L or more (P=0.0162) at baseline, and a decline of the HBV DNA level of more than 3.2 log copies/mL as compared with the baseline level at 3 mo after the start of treatment (P=0.0003) to be significantly associated with virological response. Among patients with a virological response, virological breakthrough was seen in 5.3% of 19 patients who responded virologically at 1 mo, in 20.7% of 203 patients at 3 mo, in 27.5% of 51 patients at 6 mo, in 33.3% of 12 patients at 9 mo, and in 100% of 3 patients at >=5 mo. A virological breakthrough was found significantly more often in patients with delayed virological response. CONCLUSION: Lamivudine treatment could suppress serum HBV DNA in most of the tested Japanese patients. Long-term efficacy might be seen in patients without HBeAg at baseline, in the absence of cirrhosis, and in patients with a decline in HBV DNA level soon after the start of treatment.

Adult↗
PubMed2006

Liver-targeted and peripheral blood alterations of regulatory T cells in primary biliary cirrhosis.

CD4+CD25high regulatory T cells (Tregs) play a critical role in self-tolerance, as seen in murine autoimmunity. Studies on Tregs in human autoimmunity have focused primarily on peripheral blood samples. A study targeting diseased tissue should identify direct relationships between Tregs and autoimmunity. Peripheral blood samples were collected from 91 patients with primary biliary cirrhosis (PBC), 28 immediate relatives, and 41 healthy controls, and Treg frequencies were determined as a percentage of CD4+CD25high T cells in CD4+TCR-alphabeta+ T cells. A tissue-targeted determination of frequency and distribution of FoxP3+ Tregs was also performed on 90 different liver tissue specimens exhibiting PBC (n = 52), chronic hepatitis C (CHC) (n = 30), and autoimmune hepatitis (AIH) (n = 8). Treg suppression studies were performed on 50 PBC patients and 27 controls. Patients with PBC demonstrated a relative reduction of Tregs compared with controls (P < .0002). Interestingly, a deficiency in CD4+CD25+ Tregs was also found in the daughters and sisters of PBC patients compared with controls (P < .0007). However, functional studies did not reveal a global PBC Treg defect. The level of FoxP3-expressing Tregs was markedly lower in affected PBC portal tracts compared with CHC and AIH (P < .001). In addition, the CD8+T cell/FoxP3+ Treg ratio was significantly higher in livers of late-stage PBC compared with those of CHC (P < .001) and early-stage AIH (P < .001). In conclusion, these data provide support for a genetic modulation of Treg frequency and illustrate the role Tregs play in the loss of tolerance in PBC.

Autoimmunity↗
PubMed2006

Autoreactive T-cell responses in primary biliary cirrhosis are proinflammatory whereas those of controls are regulatory.

BACKGROUND & AIMS: Autoreactive T cells that proliferate in response to autoantigens are found in both autoimmune disease and controls but have important qualitative differences in relative activation states, costimulation signal requirements, and pathogenetic significance. Understanding the mechanism for activation of autoreactive T cells will be critical in the treatment of autoimmune diseases. METHODS: To understand the differences between autoreactive T cells in primary biliary cirrhosis (PBC) versus controls, we have developed autoreactive T-cell clones (TCCs) from patients with PBC and healthy controls and have used a peptide corresponding to the CD4 major autoepitope to define the relative proliferative and cytokine response. RESULTS: Using an enzyme-linked immunosorbent spot assay, peripheral blood mononuclear cells (PBMCs) from PBC, but not from controls, produce interferon (IFN)-gamma regardless of whether costimulation-competent or -incompetent antigen-presenting cells (APC) were used. In contrast, a significant number of IFN-gamma-producing cells were found in PBMCs from controls but only if costimulation-competent PBMCs presented an autoantigenic peptide. In addition, costimulation-dependent autoreactive TCCs became anergic after a single round of stimulation in the presence of APC that did not provide a costimulatory signal, whereas some costimulation-independent autoreactive TCCs required repeated stimulation to become anergic and the others did not become anergic. Finally, anergic TCCs produced interleukin-10, but no IFN-gamma, and exhibited regulatory functions in an antigen-dependent, cell contact-independent, and partially interleukin-10-mediated manner. CONCLUSIONS: These data relate specifically to the functional characteristics of autoreactive T cells in PBC but are also generically important for understanding the mechanisms for generating pathogenetic autoreactive T cells.

Autoantigens↗
PubMed2006

Human intrahepatic biliary epithelial cells function in innate immunity by producing IL-6 and IL-8 via the TLR4-NF-kappaB and -MAPK signaling pathways.

BACKGROUND: Human intrahepatic biliary epithelial cells (HIBECs) may play active roles in both the innate and adaptive immune responses. Little is known, however, about the role of toll-like receptors (TLRs) on HIBECs in inflammatory cholangiopathies. METHODS: The expression of TLR1-9 and the biological responses to their ligands, lipopolysaccharide (LPS) or lipoteichoic acid (LTA), were studied in cultured HIBECs by reverse transcription-polymerase chain reaction, immunoblotting, and enzyme-linked immunosorbent assay. RESULTS: HIBECs constitutively expressed transcripts encoding TLR1-6 and 9, as well as myeloid differentiation factor 88 (MyD88), MD2, and CD14. Stimulation of HIBECs with LPS resulted in translocation of NF-kappaB subunits from the cytoplasmic to the nuclear fraction, followed by increased secretion of a variety of chemokines/cytokines, including interleukin-8 (IL-8), monocyte chemotactic protein-1 (MCP-1), and IL-6. Treatment with BAY11-7082 efficiently inhibited the LPS-induced transcription and secretion of these chemokines/cytokines. In HIBECs, the mitogen-activated protein kinases (MAPKs) were also activated by LPS stimulation. These results indicated that LPS activates HIBECs via a TLR4-MyD88-dependent pathway. Stimulation of HIBECs with LTA induced the secretion of a similar profile of cytokines/chemokines via a TLR2-MyD88-dependent pathway. CONCLUSIONS: In HIBECs, at least TLR2 and 4 are capable of mediating innate immune system function in vitro. This result, in conjunction with our recent finding that TLR4 expression is increased in biliary epithelial cells in primary biliary cirrhosis, suggests the involvement of TLRs in the development of chronic inflammatory cholangiopathies.

Bile Duct Diseases↗
PubMed2005

Increased expression of nuclear envelope gp210 antigen in small bile ducts in primary biliary cirrhosis.

The sustained antibody response to nuclear envelope gp210 antigen indicates a group of primary biliary cirrhosis (PBC) patients at high risk for the progression to end-stage hepatic failure. To address this issue, we immunohistochemically studied the expression of gp210 antigen in needle liver biopsy specimens from PBC patients using a monoclonal antibody specific for gp210 antigen. The specimens from autoimmune hepatitis (AIH), chronic viral hepatitis B (CHB) and C (CHC) patients served as disease controls. The expression of gp210 antigen was apparently increased on the nuclear envelope of biliary epithelial cells (BECs) of small bile ducts in almost all specimens from PBC. In contrast, the expression of gp210 antigen was negative in BECs of small bile ducts in normal liver, while relatively weak anti-gp210 immunostaining was observed in AIH, CHC and CHB. In addition, the degree of gp210 expression in BECs of small bile ducts was positively correlated to that of portal inflammation, interface hepatitis and lobular inflammation in PBC. These results indicate that the increased expression of gp210 in small bile ducts, which is probably associated with damage to BECs by inflammation, is possibly involved in autoimmune response to gp210 leading to the progression to end-stage hepatic failure in PBC.

Adult↗
PubMed2005

Relationship between body surface area and ALT normalization after long-term lamivudine treatment.

AIM: To further evaluate the relationship between BSA and the effects of lamivudine in a greater number of cases and over a longer period of observation than in our previous evaluation. METHODS: We evaluated 249 patients with chronic hepatitis B. The effects of treatment for one year (n = 249), two years (n = 147), and three years (n = 72) were evaluated from the levels of serum ALT and HBV-DNA, as biological and virological effects (undetectable levels by PCR), respectively. Moreover, several variables that could influence the response to treatment, including ALT, albumin, bilirubin, platelet counts, BSA, HBV-DNA, and HBeAg were analyzed. RESULTS: For 1-year treatment, multivariate analysis revealed that BSA (P = 0.0002) was the only factor for the biological effect, and that ALT (P = 0.0017), HBV-DNA (P = 0.0004), and HBeAg (P = 0.0021) were independent factors for the virological effect. For 2-year treatment, multivariate analysis again showed that BSA (P = 0.0147) was the only factor for the biological effect, and that ALT (P = 0.0192) and HBeAg (P = 0.0428) were independent factors for the virological effect. For 3-year treatment, multivariate analysis, however, could not reveal BSA (P = 0.0730) as a factor for the normalization of ALT levels. CONCLUSION: BSA is a significant predictor for the normalizing the effect of lamivudine therapy on ALT for an initial 2-year period, suggesting that lamivudine dosage should be based on the individual BSA.

Adolescent↗
PubMed2005

T cell immunity and graft-versus-host disease (GVHD).

Graft-versus-host disease (GVHD), induced by the reaction of donor T cells to recipient histoincompatible antigens, is a serious complication of allogeneic bone marrow transplantation (BMT), resulting in considerable morbidity and mortality. In MHC-disparate BMT, donor T cells directly react with major histocompatibility complex (MHC) antigens, while in MHC-matched BMT, T cells react with minor histocompatibility antigens (miHA) presented by shared MHC molecules. Clinically, acute and chronic GVHD can be distinguished on the basis of the time of onset, clinical manifestations and distinct pathobiological mechanisms. Acute GVHD usually occurs within 2 to 6 weeks following allogeneic BMT and primarily affects the skin, liver and the gastrointestinal tract with T cell infiltration of the epithelia of the skin, mucous membranes, bile ducts and gut. In addition, hair follicle cells, airways, bone marrow, and a variety of other tissue systems can be involved. Acute GVHD occurs in up to 50% of allogeneic HLA-matched and 70% of HLA-disparate BMT recipients despite prophylactic immunosuppressive drugs. Chronic GVHD involves a wider range of organs and clinical manifestations include scleroderma, liver failure, immune complex disease, glomerulonephritis, and autoantibody formation.

Animals↗
PubMed2005

T cell immunity in autoimmune hepatitis.

T cells play a central role in the immunopathogenesis of AIH. Until recently CD4+ T cells were thought to be critical for disease development, increasing evidence has shown that CD8+ T and gammadelta T cells also play a significant role. The predisposition of certain HLA genotypes to AIH as well as the clonal expansion of a limited number of T cell receptors suggests that the presentation of a self-antigen or a molecular mimic may be responsible for the initiation of the immune response. Given the association of AIH with viral hepatitis, it is thought that the loss of tolerance begins with an infection of hepatocytes and subsequent cytolysis by CD8+ T cells. The presentation of self-antigens or molecular mimics leads to activation and clonal expansion of T cells; this process may be increased by impaired regulatory T cells and a defect in apoptosis. Ultimately T cells initiate B cell production of autoantibodies, proinflammatory cytokines and finally hepatocyte cytotoxicity.

Animals↗
PubMed2005

T cell immunity in hepatitis B and hepatitis C virus infection: implications for autoimmunity.

T cells are involved in the pathogenesis of important liver diseases including both autoimmune liver diseases and viral hepatitis. In addition to playing a crucial role in the control of hepatitis viruses, T cell responses are also responsible for the liver injury during acute and chronic phases of viral hepatitis. In this article, we reviewed current literature on T cell immunity to hepatitis B and C viruses. In addition, antigen presenting cells that are critical for T cell immunity against these viruses are also discussed. This will provide insights to the understanding of T cell immunity in autoimmune liver diseases due to the similar role of T cells in autoimmune liver diseases and viral hepatitis.

Antigen-Presenting Cells↗
PubMed2005

Biliary epithelial cells regulate autoreactive T cells: implications for biliary-specific diseases.

The biliary epithelial cell (BEC) is the target for several human immune mediated liver diseases, including primary biliary cirrhosis, but it is not always clear whether the BEC functions as an accessory cell or an antigen presenting cell, although it is well documented that BECs express high levels of human leukocyte antigen Class II, intercellular adhesion molecule-1, and lymphocyte function-associated antigen-3. To examine this issue, we established autoreactive T-cell clones from human leukocyte antigen-DR53 patients with primary biliary cirrhosis and characterized BEC function as a function of the ability of BECs to regulate T-cell activation. We report herein that BEC-mediated T-cell activation occurs partially via programmed death 1 ligands in a cell-contact-dependent manner. Further, such activation occurs via prostaglandin E2 production in a cell-contact-independent fashion. Moreover, the production of prostaglandin E2 was partially controlled by interleukin-1beta and tumor necrosis factor alpha. In conclusion, the regulatory activities of BECs are important for the maintenance of peripheral immune tolerance. Further, modulation of BEC function may be used for therapeutic modulation.

Antigen-Presenting Cells↗
PubMed2005

Fractalkine and CX3CR1 are involved in the recruitment of intraepithelial lymphocytes of intrahepatic bile ducts.

Fractalkine is a chemokine with both chemoattractant and cell-adhesive functions, and in the intestine it is involved with its receptor CX3CR1 in the chemoattraction and recruitment of intraepithelial lymphocytes. We examined the pathophysiological roles of fractalkine and CX3CR1 in normal and diseased bile ducts. Expression of fractalkine and CX3CR1 were examined in liver tissues from patients with primary biliary cirrhosis (17 cases) and controls (9 cases of primary sclerosing cholangitis, 10 cases of extrahepatic biliary obstruction, 20 cases of chronic viral hepatitis C, and 18 cases of histologically normal livers). Expression of fractalkine in biliary epithelial cells (BECs) in response to cytokine treatments was examined using a human cholangiocarcinoma cell line (HuCC-T1) and human intrahepatic BEC line. The chemotaxis of CX3CR1-expressing monocytes (THP-1) toward fractalkine was assayed using chemotaxis chambers. Fractalkine messenger RNA/protein were expressed on BECs of normal and diseased bile ducts, and their expression was upregulated in injured bile ducts of primary biliary cirrhosis. CX3CR1 was expressed on infiltrating mononuclear cells in portal tracts and on CD3(+), CD4(+), and CD8(+) intraepithelial lymphocytes of injured bile ducts in primary biliary cirrhosis. Fractalkine messenger RNA expression was upregulated in two cultured BECs on treatment with lipopolysaccharide and Th1-cytokines (interleukin 1beta, interferon gamma, and tumor necrosis factor alpha). THP-1 cells showed chemotaxis toward fractalkine secreted by cultured cells. In conclusion, Th1-cytokine predominance and lipopolysaccharide in the microenvironment of injured bile ducts resulting from primary biliary cirrhosis induce the upregulation of fractalkine expression in BECs, followed by the chemoattraction of CX3CR1-expressing mononuclear cells, including CD4(+) and CD8(+) T cells, and their adhesion to BECs and the accumulation of biliary intraepithelial lymphocytes.

Aged↗
PubMed2005

Th1 cytokine-induced downregulation of PPARgamma in human biliary cells relates to cholangitis in primary biliary cirrhosis.

Peroxisome proliferator-activated receptor-gamma (PPARgamma) is known to inhibit the production of proinflammatory cytokines. In Th1-predominant diseases, PPARgamma ligands can ameliorate clinical severity by downregulating the expression of proinflammatory cytokines. Primary biliary cirrhosis (PBC) is characterized by chronic destructive cholangitis with a Th1-predominant cytokine milieu. Unusual immune responses to infectious agents are suspected to underlie its etiopathogenesis. We examined the significance of PPARgamma in biliary inflammation in connection to PBC. To this end, we performed immunohistochemistry, quantitative polymerase chain reaction, and nuclear factor-kappaB (NF-kappaB) DNA-binding assays to clarify the intrahepatic distribution of PPARgamma and the regulation of PPARgamma by inflammatory cytokines and PPARgamma ligand in five cultured biliary cell lines including one derived from PBC liver. In liver specimens from patients with PBC, PPARgamma protein was ubiquitously expressed in intrahepatic biliary epithelium, whereas the expression of PPARgamma protein and mRNA was reduced in damaged bile ducts. PPARgamma expression in cultured cells was upregulated by interleukin-4 (IL-4; Th2-type), but downregulated by IFN-gamma (Th1-type). PPARgamma ligand negatively modulated lipopolysaccharide-induced NF-kappaB activation. Moreover, this inhibitory effect of PPARgamma ligand was attenuated by pretreatment with IFN-gamma. In conclusion, PPARgamma may be important to maintain homeostasis in the intrahepatic biliary epithelium, and its reduction in the bile ducts of PBC liver may be associated with the Th1-predominant milieu and with the development of chronic cholangitis in PBC. Immunosuppression using PPARgamma ligands may be of therapeutic benefit to attenuate biliary inflammation in PBC.

Bile Ducts↗
PubMed2005

Altered monocyte responses to defined TLR ligands in patients with primary biliary cirrhosis.

The role of the adaptive immune response, with regard to the development of autoantibodies, has been extensively studied in primary biliary cirrhosis (PBC). However, the importance of innate immunity has been noted only recently. Based on the proposed role of microorganisms in the pathogenesis of the disease, we hypothesize that patients with PBC possess a hyper-responsive innate immune system to pathogen-associated stimuli that may facilitate the loss of tolerance. To address this issue, we isolated peripheral blood monocytes from 33 patients with PBC and 26 age-matched healthy controls and stimulated such cells in vitro with defined ligands for toll-like receptor (TLR) 2 (lipoteichoic acid; LTA), TLR3 (polyIC), TLR4 (lipopolysaccharide; LPS), TLR5 (flagellin), and TLR9 (CpG-B). Supernatant fluids from the cultures were analyzed for levels of 5 different pro-inflammatory cytokines, interleukin (IL)-1beta, IL-6, IL-8, IL-12p70, and TNF-alpha. After in vitro challenge with TLR ligands, PBC monocytes produced higher relative levels of pro-inflammatory cytokines, particularly IL-1beta, IL-6, IL-8, and TNF-alpha, compared with controls. In conclusion, monocytes from patients with PBC appear more sensitive to signaling via select TLRs, resulting in secretion of selective pro-inflammatory cytokines integral to the inflammatory response that may be critical in the breakdown of self-tolerance.

Adult↗