Hidehiro Murakami

Liver Fibrosis in Patients with Chronic Hepatitis C: Noninvasive Diagnosis by Means of Real-time Tissue Elastography—Establishment of the Method for Measurement

PURPOSE To prospectively measure liver stiffness with real-time tissue elastography in patients with chronic hepatitis C and to compare the results with those of clinical assessment of fibrosis by using histologic stage as the reference standard. MATERIALS AND METHODS All subjects gave informed consent, and the study was approved by the institutional ethics committee. Seventy hospitalized patients (46 men, 24 women; mean age, 65.5 years ± 11.7 [standard deviation]; age range, 33-87 years) with chronic hepatitis C underwent real-time elastography between January 2009 and September 2009. Elastography was performed at four liver locations by two independent observers. The elastic ratio (ratio of the value in the intrahepatic venous small vessels divided by the value in the hepatic parenchyma) was calculated and was compared with histologic fibrosis stage at liver biopsy. The elastic ratio and clinical fibrosis markers were assessed by using receiver operating characteristic (ROC) analysis. The differences between body site and observers were assessed with κ statistics and intraclass correlation coefficients (ICCs). RESULTS Real-time tissue elastography cutoff values were 2.73 for F of 2 or greater, 3.25 for F of 3 or greater, and 3.93 for F of 4. No site differences were observed (κ = 0.835, ICC = 0.966), and the elastic ratio measurement was correlated between the two examiners (r(2) = 0.869, P < .0001). The areas under the ROC curves for elastic ratio, hyaluronic acid, type IV collagen, aspartate aminotransferase-to-platelet ratio index, FibroIndex, Forns score, and Hepascore were 0.95, 0.32, 0.73, 0.76, 0.76, 0.87, and 0.70, respectively; the elastic ratio performed better than the serum fibrosis markers and other scores. CONCLUSION Real-time tissue elastography is not invasive and could be used to evaluate liver fibrosis in patients with chronic hepatitis C. SUPPLEMENTAL MATERIAL http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10100319/-/DC1.

Macrophage migration inhibitory factor in the sera and at the colonic mucosa in patients with ulcerative colitis: clinical implications and pathogenic significance.

Background Inflammatory cytokines produced by activated macrophages are implicated in the pathogenesis of ulcerative colitis (UC). With the theory that macrophage migration inhibitory factor (MIF) may have a role in the accumulation of macrophages, we studied MIF in UC.

Macrophage migration inhibitory factor activates antigen‐presenting dendritic cells and induces inflammatory cytokines in ulcerative colitis

The level of macrophage migration inhibitory factor (MIF) and the functions of dendritic cells (DC) are up‐regulated in the peripheral blood, and the numbers of MIF‐expressing cells and mature DC are increased at the colonic mucosa from patients with ulcerative colitis (UC). However, a functional relationship between MIF and DC, and the role of MIF in the pathogenesis of UC, are not clear. In this study, we showed that a pure population of peripheral blood DC is a new and still unknown source of MIF. DC from UC patients produced significantly higher levels of MIF (17·5 ± 9·8 ng/ml, n = 10) compared with patients with Crohn’s disease (CD) (4·6 ± 2·5 ng/ml, n = 5, P < 0·01) and control subjects (5·0 ± 2·6 ng/ml, n = 10, P < 0·01). A double immunofluorescence study revealed the expression of MIF by CD83‐positive mature DC at the colonic mucosa from UC patients. Blood DC treated with high amounts of MIF (500 ng/ml) showed a significantly higher stimulatory capacity (43287 ± 5998 CPM, n = 5) in an allogenic mixed leucocyte reaction compared with untreated DC (27528 ± 8823 CPM, n = 5, P < 0·05). Study of intracellular cytokine expression showed that MIF induced significant levels of interleukin (IL)‐1β and IL‐8 in monocytes and DC from UC and CD patients. These results showing the capacity of MIF to induce increased functional capacity of DC, and to produce IL‐1β and IL‐8 from monocytes and DC, indicate a role of MIF in the induction and/or perpetuation of the inflammatory environment in UC.

Decreased interferon‐α production and impaired T helper 1 polarization by dendritic cells from patients with chronic hepatitis C

Patients with chronic hepatitis C (CHC) are unable to prime and maintain vigorous T cell responses that are initiated during the acute phase of hepatitis C virus (HCV) infection. As dendritic cells (DCs) induce and regulate both innate and adaptive immune responses, the aim of this study was to analyse two critical functions of DCs: firstly, production of interferon (IFN)‐α and, secondly, polarization of T helper 1 lymphocytes. The frequencies of plasmacytoid DC (PDC) and myeloid DC (MDC) were estimated in 63 patients with CHC and 34 normal controls using four‐colour flow cytometry. Circulating DCs were isolated from peripheral blood of CHC patients (n = 10) and normal controls (n = 10). These DCs were cultured with herpes simplex virus‐1 to evaluate their capacity to produce IFN‐α. The capacity of DCs to induce polarization of autologous naive CD4+ T lymphocytes to IFN‐γ‐producing effector T lymphocytes was also assessed. The frequencies of PDCs producing intracellular IFN‐α (P < 0·01) and the levels of IFN‐α in culture supernatant of PDCs (P < 0·01) were significantly lower in patients with CHC compared to those of normal controls. The numbers of MDC were significantly lower in patients with CHC (8·2 (6·0)/µl, median (interquartile range), n = 63) compared to normal control (11·7 (7·8)/µl, n = 34) (P < 0·01). Moreover, DCs from patients with CHC induced significantly lower numbers of IFN‐γ‐producing effector T lymphocytes compared to that of controls (P < 0·01). This study indicates that the low IFN‐α‐producing capacity and impaired T helper 1 polarization ability of DCs from patients with CHC might be responsible for the typical low anti‐HCV immune responses in these patients.

Macrophage migration inhibitory factor in hepatocellular carcinoma and liver cirrhosis; relevance to pathogenesis ☆

The levels of macrophage migration inhibitory factor (MIF), a proinflammatory and carcinogenic cytokine, were significantly higher in the sera from patients with hepatocellular carcinoma (HCC; 25.6+/-15.3 ng/ml, n=55) and liver cirrhosis (LC; 18.9+/-10.7 ng/ml, n=26) compared with sera from patients with gastrointestinal cancer (6.8+/-7.5 ng/ml, n=29) and normal controls (5.6+/-1.2 ng/ml, n=45; P<0.01). Hepatocytes from patients with LC and HCC, but not from chronic hepatitis, expressed very high levels of MIF. A possible association between overexpression of MIF and hepatocarcinogenesis is suggested.

Isolation and functional analysis of circulating dendritic cells from hepatitis C virus (HCV) RNA-positive and HCV RNA-negative patients with chronic hepatitis C: role of antiviral therapy

Hepatitis C virus (HCV) RNA has been localized in antigen‐presenting dendritic cells (DCs) from patients with chronic hepatitis C (CHC). DCs from patients with CHC also exhibit impaired functional capacities. However, HCV RNA in DCs and functional impairment of DCs in CHC might be independent or interrelated events. Moreover, the impact of antiviral therapy on the functions of DCs in CHC is not well documented. In order to address these issues, we took advantage of antiviral therapy in these patients. Ten patients with CHC, expressing HCV RNA in circulating DCs, became negative for HCV RNA in circulating DCs after therapy with interferon‐α and ribavirin for 4 weeks. The functions of DCs from HCV RNA+ patients (isolated before antiviral therapy) and HCV RNA– patients (isolated 4 weeks after antiviral therapy) were compared in allogenic mixed leucocyte reactions. In comparison to circulating DCs from normal control subjects, DCs from HCV RNA+ patients had a significantly decreased capacity to stimulate allogenic T lymphocytes (P < 0·01) and produce interleukin‐12 (P < 0·05). However, the allostimulatory capacity of circulating DCs from HCV RNA– patients was several‐fold higher compared to that of HCV RNA+ DCs from the same patient. DC from HCV RNA– patients also produced significantly higher levels of interleukin‐12 compared to HCV RNA+ DCs from the same patient (P < 0·01). Taken together, this study is the first to provide experimental evidence regarding the impact of HCV RNA and antiviral therapy on the function of DCs in patients with CHC.

Characteristic endoscopic features of portal hypertensive enteropathy

BackgroundDouble-balloon endoscopy (DBE) and capsule endoscopy have opened up a new field of investigation regarding the small intestine. Although DBE has been widely used for diagnosis and treatment of different lesions in the small intestine, there is a paucity of information regarding endoscopic features of the small intestine in patients with liver cirrhosis (LC).MethodsEndoscopic images of the small intestine were taken in 21 patients with LC by DBE (EN-450P5/20 or EN-450T5/W). Biopsy specimens were taken from various parts of the small intestine and examined microscopically. Different endoscopic features of the small intestine were compared in relation to the clinical parameters of these patients.ResultsErythema and telangiectasia were observed in five patients (24%) and one patient (5%), respectively. In eight patients (38%), the small intestinal mucosa was edematous, and the intestinal villi of these patients were swollen and rounded, resembling herring roe. The patients with a herring roe appearance in the small intestine had advanced LC (Child’s classification B and C), and all of them also had portal hypertensive gastropathy and portal hypertensive colopathy. In comparison with patients without a herring roe appearance in the small intestine, patients with a herring roe appearance had a significantly increased spleen volume (P < 0.05) and decreased platelet counts (P < 0.05).ConclusionsAlthough preliminary, this study indicated that DBE may be useful for detecting different types of endoscopic lesions in patients with LC. A herring roe appearance seems to be one of the characteristic features of portal hypertensive enteropathy. However, further study will be required to develop insights about its pathogenesis.

Clinical significance of B cell-activating factor in autoimmune pancreatitis.

Objectives: Overexpression of B Cell-activating factor (BAFF) is involved in autoimmunity, but little is known about its role in autoimmune pancreatitis (AIP). The aim of this study was to investigate the role of BAFF in the diagnosis and pathogenesis of AIP. Methods: Patients with AIP (n = 19) were compared with 2 disease control groups (chronic pancreatitis [n = 17] and pancreatic cancer [n = 15]) and a healthy subject group (n = 19). Serum BAFF levels were assessed using an enzyme-linked immunosorbent assay. The expressions of BAFF and BAFF receptor in the pancreatic tissue of patients with AIP were estimated using immunohistochemistry. Results: Mean serum BAFF levels were higher in the patients with AIP than in the patients with chronic pancreatitis, the patients with pancreatic cancer, and the healthy subjects (P < 0.0001 for all groups). Using the cutoff value of 1389 pg/mL, the sensitivity and specificity to differentiate AIP from disease and healthy controls were 89.5% and 92.2%, respectively. Glucocorticoid therapy decreased serum BAFF levels below 1389 pg/mL in all patients with AIP (P < 0.0001). B Cell-activating factor and BAFF receptor were expressed on cells infiltrating the pancreas of patients with AIP. Conclusions: B Cell-activating factor could be a novel marker for diagnosis and treatment response in AIP and may contribute to its pathogenesis.

Regulatory Dendritic Cells Pulsed with Carbonic Anhydrase I Protect Mice from Colitis Induced by CD4+CD25− T Cells

Inflammatory bowel disease (IBD), which is characterized by a dysregulated intestinal immune response, is postulated to be controlled by intestinal self-antigens and bacterial Ags. Fecal extracts called cecal bacterial Ag (CBA) have been implicated in the pathogenesis of IBD. In this study, we identified a major protein of CBA related to the pathogenesis of IBD and established a therapeutic approach using Ag-pulsed regulatory dendritic cells (Reg-DCs). Using two-dimensional gel electrophoresis and MALDI-TOF mass spectrometry, carbonic anhydrase I (CA I) was identified as a major protein of CBA. Next, we induced colitis by transfer of CD4+CD25− T cells obtained from BALB/c mice into SCID mice. Mice were treated with CBA- or CA I-pulsed Reg-DCs (Reg-DCsCBA or Reg-DCsCA1), which expressed CD200 receptor 3 and produced high levels of IL-10. Treatment with Reg-DCsCBA and Reg-DCsCA1 ameliorated colitis. This effect was shown to be Ag-specific based on no clinical response of irrelevant Ag (keyhole limpet hemocyanin)-pulsed Reg-DCs. Foxp3 mRNA expression was higher but RORγt mRNA expression was lower in the mesenteric lymph nodes (MLNs) of the Reg-DCsCA1–treated mice compared with those in the MLNs of control mice. In the MLNs, Reg-DCsCA1–treated mice had higher mRNA expression of IL-10 and TGF-β1 and lower IL-17 mRNA expression and protein production compared with those of control mice. In addition, Reg-DCsCBA–treated mice had higher Foxp3+CD4+CD25+ and IL-10–producing regulatory T cell frequencies in MLNs. In conclusion, Reg-DCsCA1 protected progression of colitis induced by CD4+CD25− T cell transfer in an Ag-specific manner by inducing the differentiation of regulatory T cells.

Dendritic cell-based therapy as a multidisciplinary approach to cancer treatment: present limitations and future scopes.

Existence of residual cancers and recurrence of cancers are two major limitations of conventional therapies against cancers. A naturally-occurring defense system against tumor may be established in cancer patients by induction of antitumor immunity. Both polyvalent and tumor antigen-defined vaccines have been administered to cancer patients to accomplish this. However, the efficacy of these approaches is not promising. Dendritic cells (DCs) are regulator of the immune system. Antigens loaded on DCs (antigen-pulsed DCs) are able to induce immune responses when this can not be achieved by administration of antigens or vaccines only. Tumor antigen-pulsed DCs are now used for treatment of patients with cancers. But, it is unlikely that the present regimen of DC-based therapy would be an independent anticancer therapeutic approach. However, the therapeutic potentials of tumor antigen-pulsed DCs can be accentuated in cancer patients if this immune therapy is performed as part of multidisciplinary therapeutic approaches. In this review, we will describe about the concept and limitations of the present regimen of tumor antigen-pulsed DC-based therapy in cancer patients. We will further discuss how DC-based therapy can be applied as a multidisciplinary approach to cancer treatment.