Yoshiou Ikeda

Phase I/II study of immunotherapy using tumor antigen-pulsed dendritic cells in patients with hepatocellular carcinoma

Dendritic cells (DCs) are increasingly used as adjuvants for vaccination strategies; however, there has been very little development in DC vaccines for patients with hepatocellular carcinoma (HCC). In this study, we assessed the safety, feasibility and efficacy of a multiple tumor-associated antigen (TAA)-pulsed DC vaccine in 5 patients with advanced HCC. DCs were generated by culturing blood monocytes in the presence of granulocyte macrophage-colony stimulating factor and interleukin-4 for 5 days. The DC vaccine was prepared by pulsing DCs with cytoplasmic transduction peptide-attached α-fetoprotein, glypican-3 and MAGE-1 recombinant fusion proteins and cultivating them in the presence of maturation cocktail. DCs were injected subcutaneously near the inguinal lymph nodes, followed by topical application of toll-like receptor-7 agonist around the injection site. We showed that our DC vaccine was safe and well-tolerated over 6 vaccinations in 5 patients. All 5 patients showed T cell responses against TAAs. Clinical benefit was observed in one of the 5 patients. In conclusion, the feasibility, safety and immune activity of DCs pulsed with TAAs were confirmed in HCC patients. However, clinical response was detected only in one patient. Future trials may consider applying this therapy in a less advanced stage to obtain better clinical responses.

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.

Esophagogastric varices as a prognostic factor for the determination of clinical stage in patients with primary biliary cirrhosis

BackgroundPrimary biliary cirrhosis (PBC) is usually classified as either asymptomatic PBC (a-PBC) or symptomatic PBC (s-PBC). Although the proportion of a-PBC versus s-PBC patients has been consistently increasing, it is not clear whether the present criteria for the staging of PBC are optimal or not. We investigated the clinical stage of PBC patients from the standpoint of esophagogastric varices (EGV).MethodsOne hundred and nine PBC patients were enrolled in this retrospective study. We investigated the clinical features of PBC based on laboratory data, histological stage, symptoms, and existence of EGV. In addition, the clinical course and prognosis in patients who were periodically followed up were also studied.Results(1) EGV was detected in a-PBC patients, and there was no difference in the grade of EGV between a-PBC and s-PBC patients. (2) a-PBC patients with EGV had more liver damage than those without EGV, and a-PBC patients with EGV had a poorer prognosis than those without EGV. (3) Three of 11 patients who progressed from a-PBC to s-PBC within 3 years had EGV. (4) One of 3 a-PBC patients with EGV had progressed to s-PBC at 3-year follow-up.ConclusionsThese results indicate that EGV is one of the most important factors for evaluating PBC. Therefore, we would like to propose that a-PBC patients with EGV should either be included in the presently defined s-PBC class, or that new prognostic classes of PBC be created that include EGV as a prognostic factor.

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.

A relationship between motilin and growth hormone secretagogue receptors

The motilin receptor (MR) belongs to a family of Class I G protein-coupled receptors that also includes growth hormone secretagogue receptor (GHSR). Their potentially unique structure and the molecular basis of their binding and activation are not yet clear. We previously reported that the perimembranous residues in the predicted extracellular loops and amino-terminal tail of the MR were important for responses to the natural peptide ligand, motilin, and the transmembrane domains of the MR were important for a non-peptidyl ligand, erythromycin. We also reported that the perimembranous residues in the second extracellular loop of the GHSR were critical for natural ligand ghrelin binding and activity. The MR is 52% identical to GHSR, with 86% sequence identity in the transmembrane domains. In the current work, to gain insight into a relationship between MR and GHSR, we studied functional responses to motilin, erythromycin and ghrelin of expression cells of chimeric constructs of MR and GHSR and co-expression cells of both MR and GHSR. We also generated human MR transgenic mice, and clarified a relationship between motilin and ghrelin. MR(1-62)/GHSR(68-366) construct responded only to ghrelin, MR(1-102)/GHSR(108-366) responded to ghrelin and erythromycin, and MR(1-129)/GHSR(135-366) and MR(1-178)/GHSR(184-366) responded to erythromycin, while GHSR(1-183)/MR(179-412) responded to neither motilin, erythromycin nor ghrelin. MR and GHSR co-expression cells have no additional responses to these ligands. Motilin or erythromycin administration to human MR transgenic mice resulted in a decrease of serum acyl-ghrelin levels, while MR and GHSR mRNA expression in the gastrointestinal tracts were not changed. These data suggested that in species expressing both motilin-MR and ghrelin-GHSR, there is a compensatory relationship in vivo.

Oral administration of carbonic anhydrase I ameliorates murine experimental colitis induced by Foxp3−CD4+CD25− T cells

IBDs are thought to involve uncontrolled innate and adaptive immunity against intestinal self‐antigens and bacterial antigens. Mouse CA I is a major cecal bacterial antigen in fecal extracts and is implicated in the pathogenesis of IBD. We show here that oral tolerization to CA I induced antigen‐specific protection from intestinal inflammation in a murine model. Oral administration of CA I but not irrelevant antigen (KLH) ameliorated CD4+CD25− T cell transfer murine colitis and DSS‐induced murine colitis. Next, we investigated the mechanisms involved in the therapeutic effects of oral administration, such as induction of ALDH1a2, transcription factors, cytokines, CD103+CD11c+ DCs, and generation of Tregs. Oral administration of CA I induced ALDH1a2 mRNA expression in the MLN and colon. When compared with PBS‐treated mice, CA I‐treated mice had higher Foxp3+CD4+CD25+ Treg and CD103+CD11c+ DC numbers in the MLN and colon; had higher TGF‐β production in the MLN and colon; had lower RORγt mRNA expression in the MLN and colon; and had lower IL‐17 mRNA expression and production in the MLN. These results demonstrate that oral administration of CA I induced antigen‐specific immune tolerance by generating Foxp3+CD4+CD25+ Tregs and inhibiting Th17 cells in a murine colitis model, thus suggesting that oral tolerization with CA I is an effective therapeutic strategy for IBD regulation.

Infection as a risk factor in the pathogenesis of primary biliary cirrhosis: Pros and cons

Primary biliary cirrhosis (PBC) is a chronic and slowly progressive cholestatic liver disease of autoimmune etiology, characterized by injury of the intrahepatic bile ducts that may eventually lead to cirrhosis and liver failure. Evidence suggests cardinal roles for both environmental factors and genetic susceptibility. Nevertheless, the absolute etiology of PBC is unclear, despite recent well-designed case-control studies that reported environmental risk factors, including infectious agents, for PBC. Of the reported infectious agents, some of them are not reproducible and remain controversial. However, infection is no doubt one of the major risks among the environmental factors. This is supported by the fact that infectious agents in autoimmune diseases express antigens resulting in molecular mimicry and xenobiotics that play a role in breaking tolerance. Taken together, recent findings from genome wide assays as well as novel animal models may enable us to better understand the mechanism of pathogenesis responsible for this disease.

Earlier recurrence of esophageal varices, following therapy, in patients with primary biliary cirrhosis (PBC) compared with non-PBC patients.

BackgroundVariceal bleeding is a common, life-threatening complication of primary biliary cirrhosis (PBC). Recently, several reports have suggested that the existence of esophageal varices in patients with PBC is a significant factor in the assessment of disease prognosis. However, there have been no reports on the recurrence of esophageal varices following treatment in patients with PBC. In this study, we investigated the recurrence of esophageal varices in PBC patients and attempted to identify predictive factors for the recurrence of esophageal varices.MethodsBetween April 1993 and August 2003, 138 patients with esophageal varices who had been treated by endoscopic variceal ligation (EVL; 96 men and 42 women; age, 33–83 years; mean, 62.6 ± 10.1 years), were enrolled in the present study. The diagnosis of esophageal varices was made by upper gastrointestinal endoscopy, and the varices were graded according to the criteria of the Japanese Research Society for Portal Hypertension. The relationship between the recurrence of esophageal varices and factors such as biochemical and hematological parameters, as well as the etiology of the liver disease, was analyzed using the Kaplan-Meier method and the multivariate Weibull regression model.ResultsPBC patients had an earlier recurrence of esophageal varices compared to non-PBC patients, and two factors, prothrombin time and etiology (PBC/non-PBC), were indicative of significantly earlier recurrence of esophageal varices.ConclusionsWe should be extra careful in the follow-up of patients with PBC after therapy for esophageal varices.

An unusual case of subclinical diffuse glucagonoma coexisting with two nodules in the pancreas: characteristic features on computed tomography.

A lesion was discovered in the tail of the pancreas by ultrasonography performed during a health checkup for a 59-year-old Japanese man. Abdominal contrast-enhanced computed tomography (CE-CT) revealed strong enhancement in a 4-cm tumor in the pancreatic tail and in a 1-cm tumor in the pancreatic body. Serum glucagon levels were elevated to 54,405 pg/mL and a preoperative diagnosis of glucagonoma was made. The pancreatic tail and spleen were resected en bloc, along with a protruding tumor in the pancreatic body. However, histopathological evaluation revealed diffuse glucagonoma throughout the pancreas. When we retrospectively reviewed abdominal CE-CT after the operation, the entire pancreas was seen to be enlarged and diffusely enhanced by strong spots. Immunohistochemical examination using anti-CD31 demonstrated rich microvessels in two solid glucagonomas as well as microglucagonoma throughout the entire pancreas, indicating hypervascularity. Enlarged pancreas and diffuse enhancement of the pancreas by strong spots may be characteristic features of diffuse glucagonoma on abdominal CE-CT.

Comparison between real‐time tissue elastography and vibration‐controlled transient elastography for the assessment of liver fibrosis and disease progression in patients with primary biliary cholangitis

Assessing disease progression in patients with primary biliary cholangitis (PBC) is necessary in order to evaluate therapeutic effectiveness. Therefore, the aims of this study were to evaluate both the diagnostic accuracy of both real‐time tissue elastography (RTE) and vibration‐controlled transient elastography (VCTE), and the usefulness of hepatic and splenic elasticity as predictive markers for the progression of symptomatic PBC.