Hepatitis E virus infection and acute-on-chronic liver failure in West Africa: a case-control study from The Gambia.

BACKGROUND: In sub-Saharan Africa, it is unknown whether hepatitis E virus (HEV) infection is a common precipitating event of acute-on-chronic liver failure (ACLF). AIMS: To estimate the prevalence of HEV infection in general population and assess whether HEV is a common trigger of ACLF in cirrhotic patients in The Gambia, West Africa. METHODS: We first conducted an HEV sero-survey in healthy volunteers. We then tested cirrhotic patients with ACLF (cases) and compensated cirrhosis (controls) for anti-HEV IgG as a marker of exposure to HEV, and anti-HEV IgA and HEV RNA as a marker of recent infection. We also described the characteristics and survival of the ACLF cases and controls. RESULTS: In the healthy volunteers (n = 204), 13.7% (95% CI: 9.6-19.2) were positive for anti-HEV IgG, and none had positive HEV viraemia. After adjusting for age and sex, the following were associated with positive anti-HEV IgG: being a Christian, a farmer, drinking water from wells, handling pigs and eating pork. In 40 cases (median age: 45 years, 72.5% male) and 71 controls (39 years, 74.6% male), ≥70% were infected with hepatitis B virus. Although hepatitis B flare and sepsis were important precipitating events of ACLF, none had marker of acute HEV. ACLF cases had high (70.0%) 28-day mortality. CONCLUSIONS: Hepatitis E virus infection is endemic in The Gambia, where both faecal-oral route (contaminated water) and zoonotic transmission (pigs/pork meat) may be important. However, acute HEV was not a common cause of acute-on-chronic liver failure in The Gambia.

Increased survival of patients with end-stage hepatocellular carcinoma due to intake of ONCOXIN®, a dietary supplement.

BACKGROUND AND AIMS: Treatment and management of patients with end-stage hepatocellular carcinoma (HCC) represents a formidable challenge to contemporary branches of medical sciences. The study presented here was conducted to assess the utility of nutrient supplement, if any, for management of patients with end-stage HCC. MATERIALS AND METHODS: A total of 19 patients with end-stage HCC (Barcelona Clinic Liver Cancer [BCLC] staging D) were provided with ONCOXIN® for 3 months. Another 10 patients with end-stage HCC (BCLC stage D) with similar clinical conditions received conservative management, but they did not give consent for taking ONCOXIN® (non-ONCOXIN® group). All patients of both groups were followed on regular basis until their death. STATISTICAL ANALYSIS: The results were expressed as mean and standard deviation. Comparison between groups was performed using Student's t-test or the Mann-Whitney U test. For categorical data, Chi-square or Fisher exact test was applied. RESULTS: All patients of the control group (non-ONCOXIN® group) (10 of 10 patients) died within 2 months after study commencement. On the other hand, 10 of 19 patients receiving ONCOXIN® died within 2 months (less than 53% patients) after the start of taking ONCOXIN® (P < 0.05, compared with patients of non-ONCOXIN® group). Five more patients died within 5 months after the start of intake of ONCOXIN®. Four patients receiving ONCOXIN® survived for more than 6 months after study commencement. CONCLUSIONS: Although this is a preliminary report, it inspires considerable optimism about safety and efficacy of a food supplement for management of patients with end-stage HCC.

Hepatic necroinflammation and severe liver fibrosis in patients with chronic hepatitis B with undetectable HBV DNA and persistently normal alanine aminotransferase.

Both consensus and controversy remains regarding surrogacy of hepatitis B virus (HBV) deoxyribonucleic acid (DNA) and alanine aminotransferase (ALT), however, these markers are used to ascertain the extent of liver damages and to guide therapeutic options in patients with chronic hepatitis B. However, little is known about liver histology of patients with chronic hepatitis B with undetectable HBV DNA and persistently normal ALT. Thirty-five incidentally-detected patients with chronic HBV infection (assessed by expression of hepatitis B surface antigen for more than 6 months) with undetectable HBV DNA and normal serum ALT were enrolled in this study. Liver biopsy specimens were taken from all patients and the extent of hepatic necroinflammation and liver fibrosis were evaluated. Moderate degree of hepatic necroinflammation was detected in 2 of 35 patients and severe hepatic fibrosis was seen in 6 of 35 patients. Two patients with undetectable HBV DNA and sustained normal ALT had moderate hepatic necroinflammation and severe hepatic fibrosis. In spite of undetectable HBV DNA for prolonged period and persistently normal ALT, some patients with chronic hepatitis B express evidences of progressive liver diseases. Large scale studies in different races and geographical regions should be accomplished to develop insights about management of these patients. Studies about extent of liver diseases in these patients should be accomplished in Treatment recommendation and management strategies should be developed for these patients.

Hepatitis B surface antigen-negative, but HBV DNA-positive patients in Bangladesh.

Hepatitis B surface antigen (HBsAg) is regarded as sole marker of hepatitis B virus (HBV) infection in Bangladesh and most other developing countries. However, some HBV-negative subjects may harbor HBV DNA and transfusion of their blood may cause HBV infection in recipients. HBV DNA was checked in 20 patients with cryptogenic liver cirrhosis, 10 patients with hepatocellular carcinoma without any known etiology, and 10 apparently healthy subjects with elevated levels of serum alanine aminotransferase (ALT). HBV DNA was detected in 8 of 20 patients with cryptogenic liver cirrhosis, 1 of 10 patients with hepatocellular carcinoma, and 2 of 10 apparent healthy subjects with elevated ALT. However, all of them were negative for HBsAg in the sera. This study indicates that some additional mechanisms should be developed for detection of HBsAg-negative HBV-infected subjects for efficient control and management of HBV infection in Bangladesh.

Immunosuppressive functions of hepatic myeloid-derived suppressor cells of normal mice and in a murine model of chronic hepatitis B virus.

The immunosuppressive state of tumour-bearing hosts is attributable, at least in part, to myeloid-derived suppressor cells (MDSC). However, the role of MDSC in physiological conditions and diseases other than cancer has not been addressed. As the liver is a tolerogenic organ, the present study attempted to localize and assess functions of hepatic MDSC in a normal liver and in a murine model of chronic hepatitis B virus (HBV) infection. MDSC was identified in the liver of normal mice and HBV transgenic mice (TM) as CD11b(+) Gr1(+) cells by dual-colour flow cytometry. Highly purified populations of MDSC and their subtypes were isolated by fluorescence-activated cell sorting. The functions of MDSC and their subtypes were evaluated in allogenic mixed lymphocyte reaction (MLR) and hepatitis B surface antigen (HBsAg)-specific T cell proliferation assays. Normal mice-derived liver MDSC, but not other myeloid cells (CD11b(+) Gr1(-) ), suppressed T cell proliferation in allogenic MLR in a dose-dependent manner. Alteration of T cell antigens and impaired interferon-γ production seems to be related to MDSC-induced immunosuppression. In HBV TM, the frequencies of liver MDSC were about twice those of normal mice liver (13·6±3·2% versus 6·05±1·21%, n=5, P<0·05). Liver-derived MDSC from HBV TM also suppressed proliferative capacities of allogenic T cells and HBsAg-specific lymphocytes. Liver MDSC may have a critical role in maintaining homeostasis during physiological conditions. As liver MDSC had immunosuppressive functions in HBV TM, they may be a target of immune therapy in chronic HBV infection.

Mechanism of restoration of immune responses of patients with chronic hepatitis B during lamivudine therapy: increased antigen processing and presentation by dendritic cells.

Restoration of host immunity has been reported in patients with chronic hepatitis B (CHB) after treatment with lamivudine; however, the underlying mechanisms of this treatment have not been determined. This study examined the role of antigen-presenting dendritic cells (DC) in restoration of host immunity. Circulating DC were isolated from peripheral blood of 23 patients with CHB before and 1, 3, and 12 months after starting lamivudine therapy. The non-antigen-specific proliferation of DC was assessed in allogenic mixed leucocyte reaction. Dendritic cells were cultured with hepatitis B surface antigen (HBsAg) to prepare HBsAg-pulsed DC. Proliferative capacity and production of interleukin (IL)-12 and interferon (IFN)-γ of HBsAg-pulsed DC were evaluated. Circulating unpulsed DC and HBsAg-pulsed DC showed significantly higher levels of T-cell proliferation capacities 1 month after lamivudine therapy compared to proliferation levels before therapy (P<0.05). HBsAg-pulsed DC also produced significantly higher levels of IL-12 and IFN-γ with lamivudine therapy compared to levels before therapy (P<0.05). HBsAg-pulsed DC from lamivudine-treated patients induced proliferation of T cells of patients with CHB in an antigen-specific manner (P<0.05). However, T-cell stimulatory capacity of DC did not increase significantly 3 and 12 months after lamivudine therapy compared to 1 month after lamivudine therapy. Immune restoration as a result of lamivudine therapy is regulated at least in part by activation of DC. However, progressive activation of DC was not seen as treatment duration progressed, indicating the limitations of this mechanism of viral clearance.

Safety and immunogenicity of hepatitis B surface antigen-pulsed dendritic cells in patients with chronic hepatitis B.

The immune modulator capacity of antigen-pulsed dendritic cells (DC) has been documented in patients with cancers and in animal models of chronic viral infections. Cancer antigen-pulsed DC are now used for treating patients with cancer. But viral antigen-pulsed DC are not used in chronic viral-infected patients because safety of antigen-pulsed DC has not been evaluated in these patients. DC were isolated from human peripheral blood mononuclear cells by culturing with human-grade granulocyte-macrophage colony stimulating factor and interleukin-4. Human blood DC were cultured with hepatitis B surface antigen (HBsAg) for 8h to prepare HBsAg-pulsed DC. After immunogenicity assessment of HBsAg-pulsed DC in vitro, five million HBsAg-pulsed DC were administered intradermally to five patients with chronic hepatitis B (CHB) 1-3 times. HBsAg-pulsed DC were immunogenic in nature because they produced significantly higher levels of interleukin-12 and interferon-γ compared to unpulsed DC (P<0.05). Also, HBsAg-pulsed DC induced proliferation of HBsAg-specific T lymphocytes in vitro. CHB patients injected with HBsAg-pulsed DC did not exhibit generalized inflammation, exacerbation of liver damage, abnormal kidney function, or features of autoimmunity. Administration of HBsAg-pulsed DC induced anti-HBs in two patients and HBsAg-specific cellular immunity in 1 patient. This is the first study about preparation of antigen-pulsed DC using human consumable materials for treating patients with CHB. Because HBsAg-pulsed DC were safe for all patients with CHB and had immune modulation capacity in some patients, phase I and phase II clinical trials with antigen-pulsed DC in CHB and other chronic infections are warranted.

Swine influenza (H1N1) pandemic: developing countries' perspective.

Since the first case of the current pandemic (H1N1) 2009 virus reported to WHO on 24 April 2009 on the American continent, the virus has spread in 160 countries and territories. By mid-2009, there were 135,000 cases and 816 deaths recorded. Pandemic preparedness is not advanced in most developing countries. Effective and essential measures include heightened surveillance, early detection and appropriate medical care. The use of local resources and capacity building with the assistance of developed nations will reduce the impact of this pandemic in the developing world.

Impaired functional capacities of liver dendritic cells from murine hepatitis B virus (HBV) carriers: relevance to low HBV-specific immune responses.

The chronic hepatitis B virus (HBV) carrier exhibits ongoing replication of HBV and expresses abundant amounts of HBV-related antigens in the liver. However, HBV-specific immune responses are either absent or narrowly focused in these subjects. With the postulation that impaired functional abilities of liver dendritic cells (DCs) might be responsible for this, we assessed the functions of liver DCs in HBV transgenic mice (HBV-TM), an animal model of the HBV carrier state. Liver DCs were isolated from normal C57BL/6 mice and HBV-TM without the use of cytokines or growth factors. Lymphoproliferative assays were conducted to evaluate the ability of liver DCs to induce the proliferation of allogenic T lymphocytes and hepatitis B surface antigen (HBsAg)-enriched T lymphocytes. Liver DCs were stimulated with viral and bacterial products to assess their cytokine-producing capacities. In comparison to liver DCs from normal C57BL/6 mice, liver DCs from HBV-TM exhibited significantly decreased T cell proliferation-inducing capacities in allogenic mixed leucocyte reaction (P <0.05) and HBsAg-enriched T lymphocytes proliferation assays (P <0.05). Liver DCs from HBV-TM produced significantly lower levels of interleukin-12p70, tumour necrosis factor-alpha, interferon-gamma, and interleukin-6 (P <0.05) compared to liver DCs from normal C57BL/6 mice. This study provides evidence that liver DCs from HBV-TM had impaired ability to induce both innate and adaptive immune responses. This might account for a weak and almost undetectable HBV-specific immune response in chronic HBV carriers. This inspires hope that up-regulation of the functions of liver DCs in situ may have therapeutic implications in chronic HBV carriers.

Decreased interferon-alpha 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)-alpha 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-alpha. The capacity of DCs to induce polarization of autologous naive CD4(+) T lymphocytes to IFN-gamma-producing effector T lymphocytes was also assessed. The frequencies of PDCs producing intracellular IFN-alpha (P < 0.01) and the levels of IFN-alpha 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)/ micro l, median (interquartile range), n = 63) compared to normal control (11.7 (7.8)/ micro l, n = 34) (P < 0.01). Moreover, DCs from patients with CHC induced significantly lower numbers of IFN-gamma-producing effector T lymphocytes compared to that of controls (P < 0.01). This study indicates that the low IFN-alpha-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.

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-alpha 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.

Production and efficacy of a dendritic cell-based therapeutic vaccine for murine chronic hepatitis B virus carrierer.

Recently a new field of immunological research and clinical application of vaccines for therapeutic purposes (vaccine therapy) has been developed for treating several chronic viral infections including chronic hepatitis B virus (HBV) infection. Administration of vaccine containing hepatitis B surface antigen (HBsAg) for 1 year has resulted in negative HBsAg and development of antibody to HBsAg (anti-HBs) in some, but not in all, HBV transgenic mouse (HBV-Tg). In order to develop more potent regimen of vaccine therapy for chronic HBV carrier, we prepared a dendritic cell (DC)-based therapeutic vaccine and evaluated their therapeutic potential in HBV-Tg. DCs were isolated from single cell suspensions of murine spleen cells by collagenase digestion, density centrifugation and depletion of lymphocytes. Spleen DCs were cultured with HBsAg (100 microg) for 24 h to produce HBsAg-pulsed DCs. HBV-Tg expressing HBsAg and HBV DNA in the sera were randomly assigned to receive either HBsAg-pulsed DCs (n = 20) or unpulsed DC (n = 20) or vaccine containing HBsAg (n = 39) or complete Freund's adjuvant (n = 20) or left untreated (n = 20). Only two intraperitoneal injections of HBsAg-pulsed DCs resulted in negative HBsAg and production of anti-HBs in the sera in all HBV-Tg (n = 20). However, administration of un-pulsed DCs (n = 20) or vaccine containing HBsAg (n = 39) or only complete Freund's adjuvant did not induce negative HBsAg or production of anti-HBs in any HBV-Tg within 6 months of therapy commencement. Taken together, this study showed that HBsAg-pulsed DCs represent a highly potent therapeutic vaccine for chronic HBV infection and inspire optimism of using this vaccine in clinical conditions. A clinical trial of HBsAg-pulsed DC in patients with chronic hepatitis B is warranted.

A novel and effective approach of developing aggressive experimental autoimmune gastritis in neonatal thymectomized BALB/c mouse by polyinosinic:polycytidylic acid.

Neonatal thymectomy induces autoimmune gastritis (AIG) in 40-70% of BALB/c mice. We presumed that induction of autoimmunity by polyinosinic:polycytidylic acid (poly I:C) might allow development of a more aggressive model of AIG. A group of BALB/c mice were thymectomized on day 3 after birth. Neonatal thymectomized mice were either injected with poly I:C or phosphate-buffered saline (PBS). Non thymectomized neonatal BALB/c mice were injected with only poly I:C. All neonatal thymectomized mice injected with poly I:C developed 3 cardinal features of AIG: (1) moderate to severe degree gastritis (2) presence of autoantibody to H(+)/K(+) ATPase and (3) loss of parietal cells. However, only 70% of the PBS-treated neonatal thymectomized BALB/c mice developed some, but not, all features of AIG. A mild degree of AIG was seen in 12 of 31 nonthymectomized BALB/c mice administered with only poly I:C. Administration of poly I:C in neonatal thymectomized BALB/c mice in the first and second week appeared to be the most effective for induction of aggressive AIG. The levels of interleukin (IL)-6, IL-12p70, interferon-gamma and tumour necrosis factor-alpha were significantly higher in poly I:C-injected thymectomized mice compared to PBS-injected neonatal thymectomized mice (P < 0.05). The frequencies of CD4(+)CD25(+) regulatory T cells in the spleen were significantly decreased in neonatal thymectomized mice administered with poly I:C compared to PBS-treated neonatal thymectomized mice (P < 0.01). Taken together, these results suggest that induction of inflammatory cytokines and reduction of regulatory T cells by poly I:C might contribute to the development of an aggressive model of AIG in neonatal thymectomized BALB/c mice.

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 x 5 +/- 9 x 8 ng/ml, n = 10) compared with patients with Crohns disease (CD) (4 x 6 +/- 2 x 5 ng/ml, n = 5, P< 0 x 01) and control subjects (5 x 0 +/- 2 x 6 ng/ml, n = 10, P< 0 x 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 x 05). Study of intracellular cytokine expression showed that MIF induced significant levels of interleukin (IL)-1 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-1 and IL-8 from monocytes and DC, indicate a role of MIF in the induction and/or perpetuation of the inflammatory environment in UC.

Increased serum levels of macrophage inflammatory protein-3alpha in chronic viral hepatitis: prognostic importance of macrophage inflammatory protein-3alpha during interferon therapy in chronic hepatitis C.

Increased infiltration of lymphocytes and induction of damage and destruction of hepatocytes by these lymphocytes are characteristic features of chronic viral hepatitis. As chemokines attract lymphocytes to inflamed tissues, we studied macrophage inflammatory protein (MIP)-3alpha, a CC chemokine, in chronic viral hepatitis. The levels of MIP-3alpha were measured in the sera from 40 patients with chronic viral hepatitis and 30 control subjects by an enzyme-linked immunosorbent assay (detection limit of MIP-3alpha=7.8 pg/mL). The kinetics of MIP-3alpha were checked during interferon (IFN) therapy in 25 patients. The levels of MIP-3alpha in the sera were significantly higher in patients with chronic viral hepatitis (39.0 +/- 28.9 pg/mL) than control subjects (15.6 +/- 4.9 pg/mL; P < 0.0001) and in patients with severe (49.6 +/- 49.2 pg/mL) and moderate degree of hepatitis (50.9 +/- 27.1 pg/mL) than in mild disease (16.0 +/- 6.8 pg/mL; P < 0.05). A significant correlation was seen among serum MIP-3alpha levels with the levels of alanine aminotransferase (r=0.509, P < 0.0001), aspartate aminotransferase (r=0.505, P < 0.0001), and degrees of activity of hepatitis (r=0.592, P < 0.0001) and interface hepatitis (r=0.419, P=0.0066). The levels of MIP-3alpha were significantly increased in patients with hepatitis C 2 weeks after the start of therapy in IFN-responders, but, remained almost unchanged in IFN-nonresponders. These findings might be important not only for the understanding of immunoptahogenesis of hepatocellular damage in chronic hepatitis (CH) patients but also for a therapeutic strategy to control the local immune response in the liver. A prognostic value of MIP-3alpha during IFN therapy in patients with chronic hepatitis C is also shown.

Antigen-presenting cells at the liver tissue in patients with chronic viral liver diseases: CD83-positive mature dendritic cells at the vicinity of focal and confluent necrosis.

Although defective functions of peripheral blood or splenic antigen-presenting cells (APCs) are implicated in the pathogenesis of persistent infection in murine and human hepatitis B virus (HBV) and hepatitis C virus (HCV)-carriers, little is known regarding liver-infiltrating APCs in patients with chronic liver diseases. Using immunohistochemical methodology and antigen retrieval technique, we have detected APCs such as HLA DR-positive cells, interdigitating cells (IDCs) and CD83-positive mature and activated dendritic cells (DCs) at the liver specimens from 39 patients with chronic hepatitis (CH) and 10 patients with liver cirrhosis (LC). All 3 types of APCs were detected at the portal areas in both CH and LC, the most abundant being the HLA DR-positive APCs. CD83-positive, mature and activated DCs were detected in patients with CH around the areas of focal and confluent necrosis at the liver parenchyma in close association with T cells. The localization of CD83-positive mature and activated DCs at the liver tissues from patients with CH warrants further study about the role of these DCs in the induction of hepatocellular damage. This may also help to design DC-based therapy for patients with chronic liver diseases.