Possible pathogenetic role of ammonia in liver cirrhosis without hyperammonemia of venous blood: The so-called latency period of abnormal ammonia metabolism.

Ammonia plays a crucial role in the pathogenesis of hepatic encephalopathy. Ammonia is also involved in many other pathological conditions seen in cirrhosis, such as sarcopenia, liver fibrosis, hepatocellular injury, immune dysfunction, and hyperammonemia. Furthermore, the ammonia level of the veins is a useful prognostic factor for cirrhosis. In cirrhosis without hyperammonemia of the vein, however, covert hepatic encephalopathy has been reported. This discrepancy is because of the anatomical features of ammonia metabolism. There are two systems in the body for detoxifying ammonia: one is the urea cycle in the liver, and the other is the glutamine synthesis pathway in skeletal muscle and other tissues. The blood processed in the liver's urea cycle is then transported via arteries to various organs. Further processing occurs in the brain and skeletal muscle's glutamine synthesis pathway before entering the veins. When the urea cycle function decreases in cirrhosis, the ammonia levels in the artery increase. In response, the glutamine synthesis pathway compensates by increasing the capacity to process ammonia. Therefore, the ammonia concentration in the veins downstream of skeletal muscles does not increase immediately. However, the brain and skeletal muscles, which receive arterial blood, might be exposed to high ammonia concentrations. In addition, branched-chain amino acids in venous blood decrease. This period is the transition phase from early- to late-phase cirrhosis, and understanding the pathophysiology during this stage is extremely important for preventing the progression of cirrhosis.

Clinical factors associated with the therapeutic efficacy of atezolizumab plus bevacizumab in patients with unresectable hepatocellular carcinoma: A multicenter prospective observational study.

The treatment efficiency and predictors of atezolizumab plus bevacizumab therapy for unresectable hepatocellular carcinoma in real-world practice have not been established. This study aimed to assess the efficacy and safety of atezolizumab plus bevacizumab and to investigate predictors of progression-free survival and overall survival. Patients with unresectable hepatocellular carcinoma treated with atezolizumab plus bevacizumab therapy in 19 hospitals were enrolled before treatment and observed prospectively. The outcomes of 222 patients in this cohort were analyzed. The objective response rate and disease control rate were 22.0% and 70.6%, respectively, whereas the median progression-free survival was 5.7 months. Independent risk factors for shortened progression-free survival were younger age (<75 years; 3.9 months vs. 8.6 months), higher number of intrahepatic tumors (≥5; 4.0 months vs. 7.9 months), macrovascular invasion (2.3 months vs. 6.7 months), and higher neutrophil-to-lymphocyte ratio (≥3.03; 3.0 months vs. 7.8 months). The median overall survival was not reached; however, independent risk factors for shortened overall survival were absence of hyperlipidemia, higher number of intrahepatic tumors (≥5), macrovascular invasion, higher α-fetoprotein level (≥400 ng/mL), worse Child-Pugh score (≥6), and higher neutrophil-to-lymphocyte ratio (≥3.03). Severe adverse events (grade ≥3) were observed in 96 patients (36.0%), with proteinuria being the most frequent. In conclusion, patients with older age, lower number of intrahepatic tumors, absent macrovascular invasion, and lower neutrophil-to-lymphocyte ratio are expected to have better progression-free survival with atezolizumab plus bevacizumab therapy for unresectable hepatocellular carcinoma.

Zinc transporter 1 expression in hepatocellular carcinoma correlates with prognosis: A single-center retrospective study.

OBJECTIVES: Zinc is crucial in the pathogenesis of hepatocellular carcinoma; however, no reports have examined its association with clinical parameters and zinc transporter 1 (ZNT1) expression intensity. This study aimed to assess the association between ZNT1 expression and prognosis in patients with hepatocellular carcinoma. METHODS: This retrospective study included 65 patients who underwent surgical hepatocellular carcinoma resection at a single center between January 2011 and June 2015. ZNT1 expression on hepatocellular carcinoma cells from specimens was assessed using immunohistochemistry, and the relationship between its intensity and various clinical indexes was examined with univariate and multivariable analyses and the Mann-Whitney U, Kruskal-Wallis, Bonferroni, and log-rank tests. RESULTS: ZNT1 expression on the hepatocellular carcinoma cell membrane was negative in 31 patients and positive in 34 patients, including nine patients showing strongly positive expression. Patients with and without ZNT1 expression had similar blood zinc concentrations, α-fetoprotein levels, protein induced by vitamin K absence-antagonist-II levels, gross classification, maximal tumor diameters, and background liver disease. The blood zinc concentrations were significantly lower in patients with strongly positive ZNT1 expression (57.0 ± 22.1 µg/dL) than in those with positive ZNT1 expression (71.1 ± 14.2 µg/dL; P = 0.015) or those with no ZNT1 expression (72.9 ± 14.1 µg/dL; P = 0.043). Overall survival was significantly shorter in ZNT1-expressing patients than in non-expressing patients (log-rank test, P = 0.024). Multivariable analysis using the Cox proportional hazards model identified maximal tumor diameter (hazard ratio, 1.018; 95% confidence interval, 1.002-1.034; P = 0.026) and ZNT1 expression status (hazard ratio, 2.082; 95% confidence interval, 1.196-3.621; P = 0.010) as prognostic contributing factors.

Thrombospondin-2 as a Predictive Biomarker for Hepatocellular Carcinoma after Hepatitis C Virus Elimination by Direct-Acting Antiviral.

We evaluated the value of secreted glycoprotein thrombospondin-2 (TSP-2) to predict hepatocellular carcinoma (HCC) occurrence in chronic hepatitis C (CHC) patients after Hepatitis C virus (HCV) elimination by direct-acting antiviral agents (DAAs). A total of 786 CHC patients without an HCC history who achieved a sustained virological response (SVR) with DAAs were randomly assigned 2:1, with 524 patients as the derivation cohort and 262 patients as the validation cohort. Serum TSP-2 levels at the end of treatment were measured by enzyme-linked immunosorbent assay (ELISA). In the derivation cohort, the cumulative HCC rate was significantly higher in the high TSP-2 group than in the low TSP-2 group. Multivariate Cox proportional hazards analysis revealed that TSP-2, α-fetoprotein (AFP), and the fibrosis-4 (FIB-4) index were independent HCC risk factors. The area under the receiver operating characteristic curve (AUROC) of the score calculated from these three factors (AFT score) for predicting HCC was 0.83, which was significantly higher than that of each factor alone (TSP-2: 0.70, AFP: 0.72, FIB-4: 0.69). The AFT score was used to stratify patients according to the risk of HCC occurrence in the validation cohort. Lastly, in patients with a FIB-4 index < 3.25, the serum TSP-2 levels could be used to identify those patients with a high risk of HCC occurrence. Serum TSP-2 levels are a predictive biomarker of HCC occurrence in CHC patients after HCV elimination by DAA treatment. The AFT score using TSP-2, AFP, and the FIB-4 index may identify those who require HCC surveillance.

Fucosylated haptoglobin is a novel predictive marker of hepatocellular carcinoma after hepatitis C virus elimination in patients with advanced liver fibrosis.

BACKGROUND: Patients with advanced fibrosis are at risk for developing hepatocellular carcinoma (HCC) even after hepatitis C virus (HCV) elimination. We previously reported that serum fucosylated haptoglobin (Fuc-Hp) levels increase as the disease progresses from chronic hepatitis to cirrhosis and then HCC. However, it remains unclear whether serum Fuc-Hp levels can stratify the risk of HCC occurrence after a sustained virological response (SVR) is achieved with direct-acting antivirals (DAAs) in patients with advanced liver fibrosis. METHODS: Among 3,550 patients with chronic hepatitis C treated with DAAs at Osaka University Hospital and related hospitals, the stored sera of 140 patients who were diagnosed with F3 or F4 by liver biopsy before DAA treatment, achieved SVR, and had no history of HCC were available at both baseline and the end of treatment (EOT). We measured the Fuc-Hp levels in these samples. RESULTS: The median serum levels of Fuc-Hp at EOT were significantly lower than those at baseline. During the 54.4-month follow-up period, 16 of 140 patients developed HCC. Multivariate Cox proportional hazards analysis revealed that high Fuc-Hp at EOT, high body mass index (BMI), and low albumin at EOT were independent risk factors for HCC occurrence. Patients with all three factors-high Fuc-Hp, high BMI, and low albumin-had a higher incidence of HCC than patients without these factors. CONCLUSIONS: High serum Fuc-Hp levels at EOT were an independent risk factor for HCC occurrence after SVR. Combined with BMI and albumin, Fuc-Hp can stratify the risk of HCC occurrence among those with advanced fibrosis.

Transcriptomics Identify Thrombospondin-2 as a Biomarker for NASH and Advanced Liver Fibrosis.

BACKGROUND AND AIMS: NAFLD is the most common liver disease worldwide. NASH, the progressive form of NAFLD, and advanced fibrosis are associated with poor outcomes. We searched for their noninvasive biomarkers. APPROACH AND RESULTS: Global RNA sequencing of liver tissue from 98 patients with biopsy-proven NAFLD was performed. Unsupervised hierarchical clustering well distinguished NASH from nonalcoholic fatty liver (NAFL), and patients with NASH exhibited molecular abnormalities reflecting their pathological features. Transcriptomic analysis identified proteins up-regulated in NASH and/or advanced fibrosis (stage F3-F4), including matricellular glycoprotein thrombospondin-2 (TSP-2), encoded by the thrombospondin 2 (THBS2) gene. The intrahepatic THBS2 expression level showed the highest areas under the receiver operating characteristic curves (AUROCs) of 0.915 and 0.957 for diagnosing NASH and advanced fibrosis, respectively. THBS2 positively correlated with inflammation and ballooning according to NAFLD activity score, serum aspartate aminotransferase and hyaluronic acid (HA) levels, and NAFLD Fibrosis Score (NFS). THBS2 was associated with extracellular matrix and collagen biosynthesis, platelet activation, caspase-mediated cleavage of cytoskeletal proteins, and immune cell infiltration. Serum TSP-2 expression was measured in 213 patients with biopsy-proven NAFLD, was significantly higher in NASH than in NAFL, and increased parallel to fibrosis stage. The AUROCs for predicting NASH and advanced fibrosis were 0.776 and 0.856, respectively, which were comparable to Fibrosis-4 index, serum HA level, and NFS in advanced fibrosis diagnosis. Serum TSP-2 level and platelet count were independent predictors of NASH and advanced fibrosis. Serum TSP-2 levels could stratify patients with NAFLD according to the risk of hepatic complications, including liver cancer and decompensated cirrhotic events. CONCLUSIONS: TSP-2 may be a useful biomarker for NASH and advanced fibrosis diagnosis in patients with NAFLD.

[A Case of Early Gastric Cancer in the Remnant Stomach after Successful Treatment with ESD].

We report a case of early gastric cancer in the remnant stomach after successful treatment with endoscopic submucosal dissection(ESD). A 64-year-old woman had undergone distal gastrectomy, D2 dissection, and Billroth Ⅰ reconstruction for advanced gastric cancer 11 years previously. During a routine upper gastrointestinal endoscopy, an elevated lesion was detected at the lesser curvature of the upper gastric body of the remnant stomach, and biopsy indicated a Group 4 tumor. Curative en bloc resection of the lesion was achieved via ESD, although there was severe fibrosis along the suture line. The pathological result was 0-I, pT1a, tub1, 3×3 mm, UL(－), ly(－), v(－), HM0(8 mm), VM0(800 µm), indicating curative resection. Surveillance of the upper gastrointestinal tract 5 years after gastric cancer surgery enabled the early detection of the gastric cancer and curative resection with ESD.

[A Case of Superficial-Type Gastric Cancer with Metastatic Ovarian Cancer Diagnosed by Exploratory Laparotomy].

Here, we report a case of superficial-type gastric cancer with metastatic ovarian cancer(Krukenberg tumor)diagnosed by exploratory laparotomy. Chemotherapy was initiated at an early stage in this patient. A 43-year-old woman with superficialtype gastric cancer(0-Ⅱb plusⅡa), an ovarian tumor, and a solitary sclerotic bone lesion underwent exploratory laparotomy and bilateral salpingo-oophorectomy. Pathological findings showed that the resected ovarian tumor specimen contained the same type of signet ring cell carcinoma as the biopsy gastric cancer specimen; hence, the patient was diagnosed with superficial- type gastric cancer with metastatic ovarian cancer. She was treated with first-line chemotherapy(capecitabine plus oxaliplatin)15 days after exploratory laparotomy, followed by second-line chemotherapy(ramucirumab plus paclitaxel), thirdline chemotherapy(nivolumab), and fourth-line chemotherapy(irinotecan). Twenty-two months after the start of first-line chemotherapy, she finally died due to bone metastasis.

[A Case of Advanced Esophageal Cancer Successfully Treated with Multidisciplinary Therapy].

We report a case of advanced esophageal cancer that was successfully treated using chemotherapy, operation, and chemoradiotherapy. A 66-year-old man with advanced esophageal cancer(Mt, O-Is, T4[N0.7-stomach], N2, M0, Stage III)was administered chemotherapy(docetaxel[DOC], cisplatin[CDDP], and 5-fluorouracil[5-FU]: DCF). As the esophageal tumor achieved complete clinical response after 2 courses of chemotherapy, lymph node dissection and proximal gastrectomy were performed for the residual tumor. Abdominal CT 3 months after surgery revealed lymph node swelling. He was diagnosed with lymph node metastasis and was administered chemoradiotherapy. After chemoradiotherapy, liver metastasis was revealed, and he underwent immune checkpoint inhibitor immunotherapy. Despite the administration of immune checkpoint inhibitors, the liver metastasis developed, so he was treated with S-1 chemotherapy. S-1 chemotherapy resulted in a favorable response, and almost all metastatic lesions decreased. The patient is alive 12 months after S-1 chemotherapy without any signs of tumor regrowth.

[A Case of Curatively Resected Locally Advanced Cancer of the Pancreatic Body Treated by Distal Pancreatectomy with En Bloc Celiac Axis Resection after Preoperative Intensive Treatment].

A 70-year-old woman with locally advanced pancreatic body cancer invading the celiac axis underwent 4 courses of preoperative chemotherapy consisting of gemcitabine(GEM)plus nab-paclitaxel(nab-PTX)on days 1, 8, and 15 every 4 weeks, followed by radiation therapy(CRT; 50.4Gy delivered in 28 daily fractions). The tumor size was greatly diminished and levels of all tumor markers were decreased. R0resection by distal pancreatectomy with en bloc celiac axis resection(DP-CAR)was performed. The histopathologic findings showed that the effect of CRT was grade 2b(Evans' classification), and the surgical margins were histologically clear. After the surgery, S-1 was administered continuously. The patient shows no signs of recurrence 1 year after surgery.

[A case of advanced hepatocellular carcinoma successfully treated by liver resection after complete response induced by sorafenib administration].

A 50-year-old man presented to our hospital with the chief complaint of right hypochondriac pain and a palpable tumor. Advanced hepatocellular carcinoma (HCC) and chronic hepatitis B infection were diagnosed and treated by twice-repeated transcatheterarterial chemoembolization (TACE) followed by administration of entecavir. Two months after the last TACE, alpha-fetoprotein(AFP)and protein induced by vitamin K absence or antagonistII (PIVKA-II) levels had elevated, and multiple small early enhancing nodules were detected on computed tomography(CT)scan. Based on his age and liver function (Child-Pugh score A5), a full dose of sorafenib (800 mg/day) was administered. The sorafenib dose was decreased after one month to 400mg/day because of hand-foot syndrome. Following sorafenib administration, the lesions shrank markedly, and complete response (CR) according to modified Response Evaluation Criteria In Solid Tumors(mRECIST)was achieved within 4 months. Six months after sorafenib treatment was begun, recurrent HCC was detected in segment 6, near the previously treated lesion. The decreased size of the main tumor and normalization of AFP levels allowed curative surgical resection. The patient was discharged 5 days after surgery and is currently treated with a half dose of sorafenib. Thirteen months after surgery, a small early enhancing lesion is visible on postoperative CT scan, but AFP and PIVKA-II levels are still keeping in a normal range. This case demonstrates that if sorafenib treatment is effective, then subsequent surgical treatment can be reconsidered in patients with advanced HCC responding to this combined therapy.

[Hemobilia into a metallic biliary stent due to pseudoaneurysm: a case report].

A 48-year-old man with locally advanced pancreatic cancer underwent combined treatment with gemcitabine and proton radiation therapy. Because of subsequent obstruction of the common bile duct, a metallic biliary stent was placed and he received further gemcitabine chemotherapy. During chemotherapy, he developed an acute abdomen with a sudden-onset of tarry stool and jaundice. Gastroduodenoscopy revealed hemobilia from the biliary metallic stent. Contrast-enhanced abdominal computed tomography revealed the presence of a pseudoaneurysm arising from the right hepatic artery adjacent to the top of the stent. Hemostasis of the right hepatic artery pseudoaneurysm was achieved via transcatheter arterial embolization using cyanoacrylate.

TIE2-expressing monocytes as a diagnostic marker for hepatocellular carcinoma correlates with angiogenesis.

UNLABELLED: Angiogenesis is a critical step in the development and progression of hepatocellular carcinoma (HCC). Myeloid lineage cells, such as macrophages and monocytes, have been reported to regulate angiogenesis in mouse tumor models. TIE2, a receptor of angiopoietins, conveys pro-angiogenic signals and identifies a monocyte/macrophage subset with pro-angiogenic activity. Here, we analyzed the occurrence and kinetics of TIE2-expressing monocytes/macrophages (TEMs) in HCC patients. This study enrolled 168 HCV-infected patients including 89 with HCC. We examined the frequency of TEMs, as defined as CD14+CD16+TIE2+ cells, in the peripheral blood and liver. The localization of TEMs in the liver was determined by immunofluorescence staining. Micro-vessel density in the liver was measured by counting CD34+ vascular structures. We found that the frequency of circulating TEMs was significantly higher in HCC than non-HCC patients, while being higher in the liver than in the blood. In patients who underwent local radio-ablation or resection of HCC, the frequency of TEMs dynamically changed in the blood in parallel with HCC recurrence. Most TEMs were identified in the perivascular areas of tumor tissue. A significant positive correlation was observed between micro-vessel density in HCC and frequency of TEMs in the blood or tumors, suggesting that TEMs are involved in HCC angiogenesis. Receiver operating characteristic analyses revealed the superiority of TEM frequency to AFP, PIVKA-II and ANG-2 serum levels as diagnostic marker for HCC. CONCLUSION: TEMs increase in patients with HCC and their frequency changes with the therapeutic response or recurrence. We thus suggest that TEM frequency can be used as a diagnostic marker for HCC, potentially reflecting angiogenesis in the liver.

Association of enhanced activity of indoleamine 2,3-dioxygenase in dendritic cells with the induction of regulatory T cells in chronic hepatitis C infection.

BACKGROUND: Altered functions of dendritic cells (DCs) and/or increases of regulatory T cells (Tregs) are involved in the pathogenesis of chronic hepatitis C virus (HCV) infection. A tryptophan-catabolizing enzyme, indoleamine 2,3-dioxygenase (IDO), is reported to be an inducer of immune tolerance. Our aim was to clarify whether or not IDO is activated in chronic hepatitis C patients and its role in immune responses. METHODS: This study enrolled 176 patients with chronic HCV infection and 37 healthy volunteers. Serum kynurenine concentration was evaluated by high-performance liquid chromatography, and its correlation with clinical parameters was examined. Monocyte-derived DCs were prepared from the subjects and subsequently stimulated with a combination of lipopolysaccharide and interferon-gamma to induce functional IDO (defined as IDO-DCs). The phenotypes, kynurenine or cytokine production, and T-cell responses with IDO-DCs were compared between the patients and healthy volunteers. RESULTS: The serum kynurenine level in the patients was significantly higher than that in the healthy volunteers, and the level of serum kynurenine was positively correlated with the histological activity or fibrosis score. IDO activity in IDO-DCs from the patients was significantly higher than that in IDO-DCs from the volunteers. Furthermore, IDO-DCs from the patients induced more Tregs in vitro compared with those from the volunteers, and the frequency of induced Tregs by IDO-DCs was decreased with an IDO-specific inhibitor. CONCLUSIONS: Systemic IDO activity is enhanced in chronic hepatitis C patients in correlation with the degree of liver inflammation and fibrosis. In response to inflammatory stimuli, DCs from the patients tend to induce Tregs, with some of this action being dependent on IDO.

Human blood dendritic cell antigen 3 (BDCA3)(+) dendritic cells are a potent producer of interferon-λ in response to hepatitis C virus.

UNLABELLED: The polymorphisms in the interleukin (IL)-28B (interferon-lambda [IFN]-λ3) gene are strongly associated with the efficacy of hepatitis C virus (HCV) clearance. Dendritic cells (DCs) sense HCV and produce IFNs, thereby playing some cooperative roles with HCV-infected hepatocytes in the induction of interferon-stimulated genes (ISGs). Blood dendritic cell antigen 3 (BDCA3)(+) DCs were discovered as a producer of IFN-λ upon Toll-like receptor 3 (TLR3) stimulation. We thus aimed to clarify the roles of BDCA3(+) DCs in anti-HCV innate immunity. Seventy healthy subjects and 20 patients with liver tumors were enrolled. BDCA3(+) DCs, in comparison with plasmacytoid DCs and myeloid DCs, were stimulated with TLR agonists, cell-cultured HCV (HCVcc), or Huh7.5.1 cells transfected with HCV/JFH-1. BDCA3(+) DCs were treated with anti-CD81 antibody, inhibitors of endosome acidification, TIR-domain-containing adapter-inducing interferon-ß (TRIF)-specific inhibitor, or ultraviolet-irradiated HCVcc. The amounts of IL-29/IFN-λ1, IL-28A/IFN-λ2, and IL-28B were quantified by subtype-specific enzyme-linked immunosorbent assay (ELISA). The frequency of BDCA3(+) DCs in peripheral blood mononuclear cell (PBMC) was extremely low but higher in the liver. BDCA3(+) DCs recovered from PBMC or the liver released large amounts of IFN-λs, when stimulated with HCVcc or HCV-transfected Huh7.5.1. BDCA3(+) DCs were able to induce ISGs in the coexisting JFH-1-positive Huh7.5.1 cells. The treatments of BDCA3(+) DCs with anti-CD81 antibody, cloroquine, or bafilomycin A1 reduced HCVcc-induced IL-28B release, whereas BDCA3(+) DCs comparably produced IL-28B upon replication-defective HCVcc. The TRIF-specific inhibitor reduced IL-28B release from HCVcc-stimulated BDCA3(+) DCs. In response to HCVcc or JFH-1-Huh7.5.1, BDCA3(+) DCs in healthy subjects with IL-28B major (rs8099917, TT) released more IL-28B than those with IL-28B minor genotype (TG). CONCLUSION: Human BDCA3(+) DCs, having a tendency to accumulate in the liver, recognize HCV in a CD81-, endosome-, and TRIF-dependent manner and produce substantial amounts of IL-28B/IFN-λ3, the ability of which is superior in subjects with IL-28B major genotype.

Comparative analyses of regulatory T cell subsets in patients with hepatocellular carcinoma: a crucial role of CD25(-) FOXP3(-) T cells.

Regulatory T cells (Tregs) play pivotal role in cancer-induced immunoediting. Increment of CD25(high+) FOXP3+ natural Tregs has been reported in patients with hepatocellular carcinoma (HCC); however, the involvement of other type of Tregs remain elusive. We aimed to clarify whether FOXP3- Tregs are increased and functionally suppressive or not in patients with HCC. We enrolled 184 hepatitis C-infected patients with chronic liver diseases or HCC, 57 healthy subjects and 27 HCC patients with other etiology. Distinct Treg subsets were phenotypically identified by the expression of CD4, CD25, CD127 and forkhead/winged helix transcription factor (FOXP3). Their gene profiles, frequency and suppressor functions against T cell proliferation were compared among the subjects. To examine the molecules involving in Treg differentiation, we cultured naive CD4+ T cells in the presence of HCC cells and dendritic cells. We determined two types of CD4+ CD127- T cells with comparable regulatory ability; one is CD25(high+) cells expressing FOXP3 (CD25(high+) FOXP3+ Tregs) and the other is CD25- cells without FOXP3- expression (CD25- FOXP3- cells). The peripheral or intrahepatic frequency of CD25- FOXP3- Tregs in HCC patients is higher than those in other groups, of which significance is more than CD25(high+) FOXP3+ cells. Of importance, CD25- FOXP3- Tregs, but not CD25(high+) FOXP3+ cells, dynamically change in patients accompanied by the ablation or the recurrence of HCC. CD25- FOXP3- T cells with CD127- IL-10+ phenoype are inducible in vitro from naive CD4(+) T cells, in which programmed cell death 1 ligand 1, immunoglobulin-like transcript 4 and human leukocyte antigen G are involved.. In conclusion, CD25- FOXP3- Tregs with suppressive capacity are increased in patients with HCC, suggesting their distinct roles from CD25+ FOXP3+ Tregs.

Dynamics of regulatory T cells and plasmacytoid dendritic cells as immune markers for virological response in pegylated interferon-α and ribavirin therapy for chronic hepatitis C patients.

BACKGROUND: For the treatment of chronic hepatitis C, a combination of pegylated interferon-α (PEG-IFNα) and ribavirin has been widely used as a standard of care. Enhancement of immune response against hepatitis C virus (HCV) is known to be involved in the efficacy of the combination therapy. Our aim was to elucidate whether or not the frequency or function of blood cells is related to the outcome of the therapy. METHODS: Sixty-seven chronic hepatitis C patients with high viral load of HCV genotype 1 infection who underwent 48 weeks of PEG-IFNα2b and ribavirin therapy were examined. During the treatment, frequencies of myeloid or plasmacytoid dendritic cells, Th1, Th2 cells, NK cells, and regulatory T cells were phenotypically determined. RESULTS: Among the patients enrolled, 29 showed a sustained virological response (SVR), 18 a transient response (TR) and 17 no response (NR). The clinical and immunological markers were compared between the SVR and non-SVR patients, including TR and NR. Based on clinical, histological, immunological parameters, and cumulative dosage of PEG-IFNα2b and ribavirin, multivariate analyses revealed that higher platelet counts and higher regulatory T cell frequency at week 12 are indicative of SVR. Even in patients who attained complete early virological response at week 12, multivariate analyses disclosed that higher platelet counts and higher plasmacytoid dendritic cell frequency are indicative of SVR. CONCLUSIONS: In PEG-IFNα and ribavirin combination therapy for chronic hepatitis C patients, the increments of regulatory T cells and plasmacytoid dendritic cell frequency are independently related to favorable virological response to the therapy.

Comprehensive immunological analyses of colorectal cancer patients in the phase I/II study of quickly matured dendritic cell vaccine pulsed with carcinoembryonic antigen peptide.

Dendritic cell (DC) vaccine has been used to treat patients with advanced colorectal cancer (CRC). The results of vaccine-induced clinical responses have not always been satisfactory partially because of DC incompetence. In order to evaluate the feasibility of novel mature DCs for therapeutic adjuvants against CRC, we conducted clinical trials with carcinoembryonic antigen (CEA) peptide-loaded DC quickly generated with a combination of OK432 (Streptococcuspyogenes preparation), prostanoid, and interferon-α (OPA-DC). In the ten patients enrolled in this study, the OPA-DC vaccine was well tolerated and administered four times every 2 weeks except for two patients, who were switched to other treatments due to disease progression. Among the eight evaluable patients, one displayed stable disease (SD), while the remaining seven showed progressive disease (PD). In the SD patient, natural killer (NK) cell frequency and cytolytic activity were increased. In the same patient, the frequency of CEA-specific cytotoxic T cells (CTLs) increased stepwise with repetitive vaccinations; however, most of the CTLs exhibited central memory phenotype. In those with PD, NK cells proliferated well regardless of failure of response, whereas CTLs failed to do so. We concluded that the OPA-DC vaccine is well tolerated and has immune-stimulatory capacity in patients with CRC. Additional modulation is needed to attain significant clinical impact.

Impaired cytokine response in myeloid dendritic cells in chronic hepatitis C virus infection regardless of enhanced expression of Toll-like receptors and retinoic acid inducible gene-I.

Dendritic cells utilize various sets of Toll-like receptors (TLR) or cytosolic sensors to detect pathogens and evoke immune responses. In patients with hepatitis C virus (HCV) infection, a higher prevalence of various infectious diseases is reported; suggesting that innate immunity against pathogens is impaired. The aim of this study was to clarify whether the TLR and retinoic acid inducible gene-I (RIG-I) system in myeloid dendritic cells is preserved or not in chronic HCV infection. The expression of TLRs, RIG-I and its relatives were compared in myeloid dendritic cells between 39 patients and 52 healthy volunteers. The induction of type-I interferon (IFN) and inflammatory cytokines was examined in response to agonists for TLR2 (palmitoyl-3-cysteine-serine-lysine-4), TLR3/RIG-I (polyinosine-polycytidylic acid) or TLR4 (lipopolysaccharide). The relative expressions of TLR2, TLR4, RIG-I, and LGP2 from the patients were significantly higher than those from the volunteers, whereas TLR3 and MDA-5 expressions did not differ. In search for factors regulating TLR/RIG-I expression, it was shown that IFN-alpha, polyinosine-polycytidylic acid and lipopolysaccharide induced TLR3, TLR4 and RIG-I, but TNF-alpha, HCV core or HCV non-structural proteins did not. For the functional analyses, myeloid dendritic cells from the patients induced significantly less amounts of IFN-beta, TNF-alpha and IL-12p70 in response to polyinosine-polycytidylic acid or lipopolysaccharide. It is noteworthy that the expression of TRIF and TRAF6, which are essential adaptor molecules transmitting TLR3 or TLR4-dependent signals, is reduced in the patients. Thus, innate cytokine responses in myeloid dendritic cells are impaired regardless of enhanced expressions of TLR2, TLR4, and RIG-I in HCV infection.