Molecular Detection of Indigenous Hepatitis E Virus (HEV) from Tibetan Pigs in Tibet, China

Hepatitis E is an important public health concern throughout the world. Many molecular and serological surveys have reported the prevalence and genotypic characteristics of HEV in humans and animals worldwide. However, the genotypic characterization of this virus is very limited in Tibetan pigs. Hence, we aimed to explore the genotype of HEV, prevailing among Tibetan pigs in China. For this purpose, 253 bile samples of Tibetan pigs (free-range animals) were collected from different slaughterhouses during 2017-2018 and subsequently tested for HEV RNA by RT-nPCR. A total of 11 out of 253 (4.35%) samples tested were positive for HEV RNA. Based on the sequence alignment and phylogenetic analysis, all the isolated HEV strains belonged to genotype 4 and clustered into subtype 4b by sharing more than 84.8-95.2% identities with other reported strains. Our results concluded that HEV genotype 4 is prevailing among Tibetan pigs in Tibet, China.

Phylogenetic Analysis and Characterization of the Complete Hepatitis E Virus Genome (Zoonotic Genotype 3) in Swine Samples from Mexico

Hepatitis E virus (HEV) is an emerging public health problem with an estimated 20 million infections each year. In Mexico, Orthohepevirus A, genotype 2, has been reported in humans, but genotype 3 has only been reported in swine (zoonotic). No diagnostic tests are publicly available in Mexico, and only partial sequences have been reported from swine samples. Hence, research is necessary to determine circulating strains, understand the features and dynamics of infection on pig farms, determine how to implement surveillance programs, and to assess public health risks. In this study, a next-generation sequencing (NGS) approach was applied to obtain a complete genome of swine HEV. Liver, feces, and bile samples were taken at slaughterhouses and a farm in Mexico. RT-PCR was used to determine positive samples and confirmed by Sanger sequencing. Of the 64 slaughterhouse samples, one bile sample was positive (B1r) (1.56%). Of 21 sample pools from farm animals, 14 were positive (66.66%), representing all stages of production. A complete sequence strain MXCDg3_B1c|_2016 was obtained from the bile of a domestic swine in the fattening stage. In addition, two partial sequences—MXCDg3_H2cons|_2016 (1473 nt) and MXCDg3_C3Acons|_2016 (4777 nt)—were obtained from sampled farm animals. Comparison with all reported genome HEV sequences showed similarity to genotype 3 subgenotype a (G3a), which has been previously reported in acute cases of human hepatitis in the US, Colombia, China, and Japan.

Hepatitis E Virus (HEV) egress: Role of BST2 (Tetherin) and interferon induced long non- coding RNA (lncRNA) BISPR

Background

The biology of Hepatitis E Virus (HEV), a common cause of epidemic and sporadic hepatitis, is still being explored. HEV exits liver through bile, a process which is essential for its natural transmission by feco-oral route. Though the process of this polarised HEV egress is not known in detail, HEV pORF3 and hepatocyte actin cytoskeleton have been shown to play a role.

Methods

Our transcriptome analysis in Hepatitis E virus (HEV) replicon transfected Huh7 cells at 24 and 72 hrs indicated that at 24hrs, both LncBISPR and BST2, expressed by a bidirectional promoter were highly upregulated whereas at 72 hrs, BST2 expression was comparatively reduced accompanied by normal levels of BISPR. These findings were confirmed by qPCR analysis. Co-localisation of BST2 and HEV pORF2 was confirmed in HEV transfected Huh7 by confocal microscopy. To investigate the role of BISPR/BST2 in HEV life cycle, particularly virus egress, we generated Huh7 cells with ~8kb deletion in BISPR gene using Crispr-Cas9 system. The deletion was confirmed by PCR screening, Sanger sequencing and Real time PCR. Virus egress in ΔBISPR Huh7 and Huh7 cells was compared by measuring HEV positive strand RNA copy numbers in cell lysates and culture supernatants at 24 and 72 hrs post HEV replicon transfection and further validated by western blot for HEV pORF2 capsid protein.

Results

ΔBISPR Huh7 cells showed ~8 fold increase in virus egress at 24 hrs compared to Huh7 cells. No significant difference in virus egress was observed at 72hrs. Immunohistochemistry in histologically normal liver and HEV associated acute liver failure revealed BST2 overexpression in HEV infected hepatocytes and a dominant canalicular BST2 distribution in normal liver in addition to the cytoplasmic localisation reported in literature.

Conclusions

These findings lead us to believe that BISPR and BST2 may regulate egress of HEV virions into bile in vivo. This system may also be used to scale up virus production in vitro.

Detection of Torque Teno Sus Virus in Pork Bile and Liver Sausages

Torque teno viruses (TTV) are small DNA viruses widespread among humans and pigs. The clinical significance of TTV infections in either humans or pigs is uncertain. In fact, TTV viremia is highly prevalent in patients with different pathologies, but it can also be frequently observed in healthy subjects. Virus infection in pigs is considered a putative cofactor in several diseases; despite being detected frequently in healthy animals, its role still remains unknown. The present study aimed to investigate the presence of Torque teno sus virus (TTSuV) in 62 bile samples collected from pigs at slaughterhouse and in 36 fresh pork liver sausages bought at point of sale. Quantitative Real-Time PCR, confirmed that 19.4 and 58.3 % of bile and sausage samples tested positive for TTSuV, respectively. The mean viral load was established as 5.6 × 10⁴ GE/µl for bile and 7.16 × 10³ GE/g for sausages. TTSuV nucleotide sequence analysis confirmed a wide heterogeneity among the circulating TTSuV strains, which included both TTSuV1 and TTSuV2.

Seroprevalence and evolutionary dynamics of genotype 4 hepatitis E virus in Shandong Province, China

AIM: To investigate the seroprevalence and evolutionary dynamics of hepatitis E virus (HEV) and assess the ancestor of HEVs in China’s Shandong Province.

METHODS: A total of 2028 serum, 60 fecal and 82 bile samples were collected from the general human population, patients and swine, respectively. This seroepidemiological study was conducted using an immunnosorbent assay and HEV RNA was detected by the reverse transcription-nested polymerase chain reaction (RT-nPCR) method. Complete genome sequences of the prevalent strains (CH-YT-HEV01, CH-YT-HEV02 and CH-YT-sHEV01) were determined, and the sequences were analyzed phylogenetically. In addition, the evolutionary dynamics of three HEV isolates were determined using the framework of coalescent analysis in the program package BEAST, and the time of the most recent common ancestors (TMRCAs) of China-indigenous genotype 4 HEV isolates was calculated.

RESULTS: The overall viral burden in the general human population was 0.1%, and the positive rates of anti-HEV IgG and IgM in the serum specimens were 25.1% (509/2028) and 2.3% (51/2028), respectively. In addition, IgG positivity increased with age. The phylogenetic analysis based on the full-length nucleotide sequences showed that the strain CH-YT-HEV02 was directly related to CH-YT-sHEV01 with a 94% identity, suggesting that they were involved in cross-species transmission. The isolate CH-YT-HEV01 was close to HB-3 and CHN-SD-sHEV with a bootstrap value of 100%, sharing a 96.1%-96.4% identity with each other. Surprisingly, the HB-3 strain was a representative strain prevalent in swine in Hubei, and the isolate CHN-SD-sHEV was obtained from swine in Shandong in a previous report. TMRCA for the clade of CH-YT-HEV01 and HB-3 was 2003, which was consistent with the TMRCA for the clade of CHN-SD-sHEV and HB-3, and they were both earlier than the TMRCA for the clade of CH-YT-HEV01 and CHN-SD-sHEV (2004).

CONCLUSION: The strains CH-YT-HEV01, CHN-SD-sHEV and HB-3 are involved in trans-regional transmission, and the ancestors of HEVs in Shandong come from Hubei Province.

The prevalence of hepatitis E virus infections among swine, swine farmers and the general population in Guangdong Province, China

Hepatitis E virus (HEV) infection is widespread in China, but few studies have been carried out in Guangdong Province. This study aimed to characterize the prevalence of HEV infections among swine, swine farmers and the general population in Guangdong Province. We conducted an epidemiological study that included swine, swine farmers and health examination attendees in Guangdong from 2011 to 2013. The overall seroprevalence of anti-HEV antibodies in swine was 64.7%. The results revealed that growing pigs, sows and boars (OR ranges from 3.5 to 21.5) have a higher risk than nursery pigs. HEV RNA in swine bile showed that HEV is epidemic in swine in the Pearl River Delta, with the highest prevalence of 22.73% in Foshan. Some genomes of HEV strains from each district were sequenced. Phylogenetic analysis of partial open reading frame 2 (ORF2) shows that they belong to genotype IV and are most closely related to isolates from China. In total, 307 participants were enrolled in the study, including 114 swine farmers and 193 attendees from hospitals. IgG anti-HEV was detected in 48.25% of swine farmers and in 38.34% of the general population. Seroprevalence rates were almost stratified by age, with a higher positive rate for males compared to females across all age groups. Women on swine farms appeared to have a lower risk of infection compared to the general population, revealing that the risk factors for HEV infection are not unique. The results suggested that there were other risk factors for HEV infection. HEV infection is prevalent in Guangdong, but due to the small sample sizes, more investigations are needed to assess the potential impact of HEV infection, and many additional risk factors should be considered.

Simple and rapid detection of swine hepatitis E virus by reverse transcription loop-mediated isothermal amplification

Hepatitis E virus (HEV) is an enteric pathogen of humans and animals, and pigs have been considered an important reservoir of this virus. Recent evidence has indicated the cross-species transmission of hepatitis E virus (HEV) from pigs to humans, causing zoonosis, mostly via consumption of uncooked or undercooked animal meat/viscera. In this study, we have developed a one-step RT-LAMP assay for rapid detection of swine HEV. Specific primer sets targeting the ORF3 gene were designed. The sensitivity of the RT-LAMP assay was 10(1) copies/μl of RNA template, which was tenfold higher than that of RT-nPCR. The specificity of this assay was demonstrated by the lack of amplification of DNA/RNA from other swine viruses. Furthermore, a total of 41 bile samples were subjected to RT-LAMP and RT-nPCR. Eighteen positive samples were detected by RT-nPCR, while 36 positive samples were detected by RT-LAMP, indicating that the sensitivity of the RT-LAMP assay was higher than that of the conventional RT-nPCR assay. The RT-LAMP assay reported here may be used for diagnosis of swine HEV, not only in laboratories but also under field conditions.

First detection of hepatitis E virus in Austrian pigs by RT-qPCR

Long known to cause disease outbreaks in man in countries with poor sanitary conditions, an increasing number of autochthonous HEV genotype 3 infections have been reported in industrialised countries. Genotype 3 poses an important potential zoonotic threat, with infected pigs functioning as the main reservoir. This study reports the first detected emergence of HEV in Austrian pigs. Five Austrian strains were partially sequenced and phylogenetic analysis demonstrates that they cluster within genotype 3. In addition, a reverse transcription quantitative real-time PCR (RT-qPCR) method using a MGB-hydrolysis probe was developed offering the possibility to detect the HEV genotype 3 in faeces, liquid- and tissue-samples from domestic pigs. The method was adapted to the strains found in Austria. Sensitivity of the assay was tested with different pig organs (liver, mesenteric lymph nodes and kidney) as well as with serum, bile and faeces samples. Within the dynamic range of the assay, a quantitative determination of virus loads was performed. For specificity testing several common swine pathogens were used. Results demonstrated that the proposed method allows implementation of reliable high-throughput screening of Austrian swine samples in the future.

Detection of hepatitis E virus (HEV) in a demographic managed wild boar (Sus scrofa scrofa) population in Italy

Hepatitis E virus (HEV) is the causative agent of Hepatitis E. Swine and human HEV strains are genetically related, suggesting the occurrence of zoonotic transmission. Recently, in Japan, cases of food-borne HEV transmission have been described in people after consuming raw or undercooked meat from wild boars or pigs. Although, swine HEV strains have been detected in pig herds in many European countries, only minimal information is presently available about the circulation and the prevalence of HEV in wild boars in Europe. In this study, we investigated the presence of HEV in a demographic managed wild boar population in Italy. Detection of HEV RNA was accomplished using a nested reverse-transcription polymerase chain reaction on bile samples from 88 shot animals. HEV RNA was detected in 22 out of 88 animals tested (25%). Phylogenetic analysis on the nucleotide sequences obtained from 10 positive PCR products indicated that only one HEV strain was circulating in the wild boar population considered, and that this strain was closer to human and swine HEV strains circulating in Europe than to wild boar Japanese strains.

Egg whites from eggs of chickens infected experimentally with avian hepatitis E virus contain infectious virus, but evidence of complete vertical transmission is lacking

Avian hepatitis E virus (HEV) is genetically and antigenically related to human HEV. Vertical transmission of HEV has been reported in humans, but not in other animals. In this study, we showed that avian HEV could be detected in chicken egg-white samples. Subsequently, avian HEV in egg white was found to be infectious, as evidenced by the appearance of viraemia, faecal virus shedding and seroconversion in chickens inoculated with avian HEV-positive egg white, but not in chickens inoculated with HEV-negative egg white. To further assess the possibility of vertical transmission of avian HEV, batches of embryonated eggs from infected hens were hatched, and hatched chicks were monitored for evidence of avian HEV infection. However, no virus was detected in samples collected from the hatched chicks throughout this study, suggesting that avian HEV could not complete the vertical transmission cycle. The possible implications of our findings are also discussed.

Detection of hepatitis E virus in liver, mesenteric lymph node, serum, bile and faeces of naturally infected pigs affected by different pathological conditions

The objective of the present study was to detect hepatitis E virus (HEV) in different samples from naturally infected pigs and to characterise genetically the detected strains. Serum, bile, liver, lymph nodes and faeces of 69 animals from 1 week to 4 months of age with different pathological conditions were collected. Reverse transcriptase-polymerase chain reaction (RT-PCR) to detect HEV and histopathology of tissues was conducted. Positive RT-PCR samples were sequenced and phylogenetically analysed. HEV was detected in at least one sample in 26 out of 69 animals (37.7%). Bile was the most frequently positive sample, followed by mesenteric lymph nodes, liver, faeces and serum. HEV was detected in pigs of 1 (n = 7), 2 (n = 8) and 3 (n = 11) months of age. A total of 22 of 69 (31.9%) pigs had mild to moderate hepatitis and 15 of them were HEV RT-PCR positive in at least one of the tested samples. The highest sensitivity of viral detection was achieved using samples that cannot be obtained from live pigs, such as liver, mesenteric lymph node and bile. Phylogenetic analyses confirmed that all Spanish swine HEV strains detected belonged to genotype III. Therefore, genotype III strains are present in a relative high proportion of pigs between 1 and 3 months of age. Through this study, it cannot be ruled out if concomitant infections may influence the distribution of HEV in infected pigs.

HCV/PCR positivity in bile and doudenal aspiration of fascioliasis and/or HCV patients

In this study, three bile aspirates taken from 10 fascioliasis patients (30.0%) showed HCV positivity by PCR/RNA. Also, four duodenal aspirates (66.7%) taken from six HCV/PCR-RNA positive patients and three duodenal aspirates (20%) taken from 15 pure fascioliasis patients showed HCV positivity by PCR/ RNA. This is the first time to demonstrate HCV/PCR-RNA in the bile and duodenal aspirates of fascioliasis patients and in the duodenal aspirates of HCV patients. So, PCR can be used for the detection of HCV in the bile and/or duodenal aspirates of HCV suspected patient. On the other hand, this outcome results may incriminate HCV infection as a concomitant with fascioliasis or incriminate fascioliasis as paving the way to HCV.

Systematic pathogenesis and replication of avian hepatitis E virus in specific-pathogen-free adult chickens

Hepatitis E virus (HEV) is an important human pathogen. Due to the lack of a cell culture system and a practical animal model for HEV, little is known about its pathogenesis and replication. The discovery of a strain of HEV in chickens, designated avian HEV, prompted us to evaluate chickens as a model for the study of HEV. Eighty-five 60-week-old specific-pathogen-free chickens were randomly divided into three groups. Group 1 chickens (n=28) were each inoculated with 5 x 10(4.5) 50% chicken infectious doses of avian HEV by the oronasal route, group 2 chickens (n=29) were each inoculated with the same dose by the intravenous (i.v.) route, and group 3 chickens (n=28) were not inoculated and were used as controls. Two chickens from each group were necropsied at 1, 3, 5, 7, 10, 13, 16, 20, 24, 28, 35, and 42 days postinoculation (dpi), and the remaining chickens were necropsied at 56 dpi. Serum, fecal, and various tissue samples, including liver and spleen samples, were collected at each necropsy for pathological and virological testing. By 21 dpi, all oronasally and i.v. inoculated chickens had seroconverted. Fecal virus shedding was detected variably from 1 to 20 dpi for the i.v. group and from 10 to 56 dpi for the oronasal group. Avian HEV RNA was detected in serum, bile, and liver samples from both i.v. and oronasally inoculated chickens. Gross liver lesions, characterized by subcapsular hemorrhages or enlargement of the right intermediate lobe, were observed in 7 of 28 oronasally and 7 of 29 i.v. inoculated chickens. Microscopic liver lesions were mainly lymphocytic periphlebitis and phlebitis. The lesion scores were higher for oronasal (P=0.0008) and i.v. (P=0.0029) group birds than for control birds. Slight elevations of the plasma liver enzyme lactate dehydrogenase were observed in infected chickens. The results indicated that chickens are a useful model for studying HEV replication and pathogenesis. This is the first report of HEV transmission via its natural route in a homologous animal model.

Genoprevalence in human tissues of TT-virus genotype 6

TT virus (TTV) is a newly discovered human virus of high genotypic diversity. TTV is widely distributed among humans, but the possible genotype-related differences in TTV biology are not well known. The prevalence and amount of TTV-DNA, especially of genotype 6, was determined by nested-PCR in various human tissues, and human parvovirus B19, another ssDNA virus, was used as a reference. TTV DNA was detected simultaneously in bile, peripheral blood mononuclear cells (PBMC) and plasma of 77% subjects, in 38% skin samples, in 38% synovial samples and in all (100%) adenoids, tonsils and liver samples. The relative concentrations of TTV-DNA did not vary significantly among the different samples. Genotype 6 TTV-DNA was detected in bile and plasma of one subject (3%), in skin and serum of one subject (8%) and in one liver (5%). The overall prevalence of TTV genotype 6 was 4% in subjects and 4% in sera. TTV genotype 6 was shown to occur in human tissues with no obvious tissue-type or symptom specificity. Parvovirus B19 DNA was detected overall in 38% subjects, and bile was the only sample type tested that did not persistently harbour B19 DNA.

Genetic identification of avian hepatitis E virus (HEV) from healthy chicken flocks and characterization of the capsid gene of 14 avian HEV isolates from chickens with hepatitis–splenomegaly syndrome in different geographical regions of the United States

Avian hepatitis E virus (HEV), a novel virus identified from chickens with hepatitis-splenomegaly (HS) syndrome, is genetically and antigenically related to human HEV. Recently, it was found that avian HEV antibody is also prevalent in healthy chickens. A prospective study was done on a known seropositive but healthy chicken farm to identify avian HEV isolates from healthy chickens. Fourteen chickens were randomly selected, tagged and monitored under natural conditions for 19 weeks. All 14 chickens were seronegative at the beginning of the study at 12 weeks of age. By 21 weeks of age, all 14 chickens had seroconverted to avian HEV antibody. None of the chickens had any sign of HS syndrome. Partial helicase gene and capsid gene sequences of avian HEV isolates recovered from a healthy chicken were determined and found to share 75-97 % nucleotide sequence identity with the corresponding regions of avian HEV isolates from chickens with HS syndrome. Thus far, only one strain of avian HEV from a chicken with HS syndrome has been genetically characterized for its capsid gene, therefore the capsid gene region of an additional 14 isolates from chickens with HS syndrome were also characterized. The capsid genes of avian HEV isolates from chickens with HS syndrome were found to be heterogeneic, sharing 76-100 % nucleotide sequence identity with each other. This study indicates that avian HEV is enzootic in chicken flocks and spreads subclinically among chickens in the United States and that the virus is heterogeneic.

Detection of hepatitis C virus in the bile and bile duct epithelial cells of hepatitis C virus-infected patients

The pathobiology of hepatitis C virus (HCV) in the biliary system has not been clarified yet, although bile duct damage is a histological finding characteristic of chronic hepatitis C. In this study, we examined whether HCV infects bile ducts and is released into the bile. Twelve patients positive for serum HCV antibody were examined in this study, and eight were seropositive for HCV RNA by polymerase chain reaction (PCR). For those who underwent abdominal surgery, the bile was aspirated from the gall bladders by fine needle puncture. Five underwent wedge liver biopsy. Series of saline-diluted bile were assayed for HCV RNA by PCR to determine the HCV RNA titers. To examine HCV expression in the biliary system, the liver specimens were immunostained using monoclonal antibodies to the HCV proteins. HCV RNA was detected in the bile of 5 patients with high serum HCV RNA load (> or = 2.5 Meq/mL). Comparison of viral loads between serum and bile revealed that the HCV RNA level in the bile was as high as that in serum. Furthermore, immunohistological study showed that bile duct epithelial cells were infected with HCV. In contrast, HCV was not found in either the bile or bile duct of patients seronegative for HCV RNA or with low serum HCV load (< or = 1.1 Meq/mL). These findings suggest that the biliary system is involved in the pathobiology of HCV and that the bile is as highly infectious as the serum.

High prevalence of TT virus in human bile juice samples: importance of secretion through bile into feces

TT virus (TTV) is much more prevalent than we once imagined. With the use of primers designed from the noncoding regions, a more than 90% rate of TTV infection in the general population by polymerase chain reaction (PCR) has been reported, showing that nonparenteral transmission must play an important role to its epidemiology. We considered that TTV may be secreted through bile juice into feces to establish nonparenteral infection. Paired bile juice and serum samples were obtained from 26 patients who were receiving bile drainage. Feces were also recovered after the drainage tube was removed. TTV DNA was detected from 22 patients in serum (84.6%), and they were all TTV DNA positive in bile juice. Most feces samples recovered from TTV-positive patients were also TTV DNA positive. Secretion of TTV into bile juice appears to be common, and this could play an important role to its transmission and its epidemiology.

[Experimental infection of a novel nonenveloped DNA hepatitis virus in Rhesus monkey]

OBJECTIVE

To test the susceptibility of the Rhesus monkey to the TT virus and to establish its transmission route.

METHODS

Rhesus monkeys were administered orally and intravenously with the inoculum that was prepared with feces collected from a patient at the incubation period. Passage study was done with monkey' s positive feces. The blood, bile and feces were tested with polymerase chain reaction (PCR), and the liver, the jejunum tissues with in situ hybridization.

RESULTS

The viremia occurred 4-7 days after intravenous inoculation and 7-10 days after oral administration. The virus was also excreted in the feces in a few days after oral infection and simultaneously with viremia after intravenous inoculation. The virus was also detected in the bile during the viremic phase. There was a prolonged carrier state that the viremia and fecal virus excretion persisted for more than 6 months. No serum transaminase elevation was found during the infection. There were virus signals in hepatocytes in columnar epithelium and lamina propria cells of jejunum villi, but no significant pathology was demonstrated in both sites.

CONCLUSIONS

The liver infection of Rhesus monkey was established hb either oral or parenteral virus Inoculation. The virus may be released from liver into blood and intestine vial the bile or just from the gut wall into feces, and hence it may be transmitted by both routes.

Biliary excretion of TT virus (TTV)

A novel DNA virus (TT virus; TTV) was isolated from a patient with post-transfusion hepatitis of unknown etiology. If TTV replicates in the liver, TTV may appear in the bile. In the present study, to clarify whether fecal-oral infection occur via biliary excretion, the presence of TTV DNA was assessed in paired serum and bile samples collected from 28 patients with obstructive jaundice without parenchymal liver disease. TTV DNA was detected by polymerase chain reaction (PCR) using semi-nested primers, and quantified by Real Time Detection PCR (RTD-PCR). The nucleotide sequence of isolates TTV DNAs was also determined and the sequences were compared between serum and bile samples. Among 28 patients, 7 were positive for TTV DNA in both samples, and 3 and 2 were positive in serum and bile respectively. Of 7 patients positive for TTV DNA in both samples, the TTV DNA titer was higher in serum of 4 patients and in bile of 1 patient. Among 7 patients positive for TTV DNA in serum and bile, 6 had the same sequence in both samples. Multiple distinct types of TTV DNA clones were isolated from serum in 2 patients and from bile in 4 patients. In conclusion, TTV DNA is detected frequently in bile from patients with obstructive jaundice, suggesting a fecal-oral route of infection and high prevalence of asymptomatic TTV carriers. TTV DNA was detected only in serum from some patients, suggesting that replication of TTV may occur in other organs as well as in the liver.

Kaposi's sarcoma of the pancreas mimicking pancreatic cancer in an HIV-infected patient. Clinical diagnosis by detection of HHV 8 in bile and complete remission following antiviral and cytostatic therapy with paclitaxel

BACKGROUND

Diagnosis of pancreatic cancer is usually made by endoscopic retrograde cholangiopancreatography (ERCP) and corresponding findings in computed tomography (CT) or magnetic resonance imaging. Kaposi's sarcoma, a frequent tumor in individuals with a late-stage HIV infection, can be located in the gastrointestinal tract and cause identical symptoms to carcinoma of the same site. A close correlation of this tumor to human herpes virus 8 (HHV 8) has been known for several years and there are reports of successful antiproliferative therapy.

METHODS

Aspirated pancreatic juice and bile was investigated for the presence of HHV 8 by polymerase chain reaction. The clinical course of the patient under antiviral therapy and treatment with paclitaxel was studied.

RESULTS

A 47-yr-old HIV-infected man with a history of Kaposi's sarcoma of skin and lungs caused by obstructive jaundice in the years before was admitted. ERCP showed a typical double-duct sign and CT revealed a tumorous infiltration of the pancreatic head, highly suspicious for pancreatic adenocarcinoma. A mutation of the ki-ras gene could be ruled out and molecular analysis of bile identified HHV 8 by PCR. Intensive antiviral therapy, including foscarnet and treatment with paclitaxel led to a complete remission within 8 m.o.

CONCLUSION

Kaposi's sarcoma of the pancreas possibly mimics pancreatic cancer in HIV-infected subjects. Diagnosis may be made by identification of HHV 8 in pancreatic juice or bile, and successful clinical outcome is possible by intensive antiviral and cytostatic treatment with paclitaxel.

Excretion into bile of a novel unenveloped DNA virus (TT virus) associated with acute and chronic non-A-G hepatitis

Recently, an unenveloped, single-stranded DNA virus named TT virus (TTV) has been reported in association with hepatitis of non-A-G etiology. Five patients with TTV viremia, who received bile drainage or cholecystectomy, were tested for TTV DNA in bile by polymerase chain reaction with heminested primers. TTV DNA was detected in bile from all patients; titers were 10-100 times higher than in serum in 4 and at a comparable level in the remaining 1 patient. TTV DNA was detected in feces, also, in 1 of the 2 patients tested. The buoyant density of TTV in bile from 1 tested patient (1.33-1.35 g/cm3) was the same as that in feces (1.32-1.35 g/cm3). TTV may be secreted via bile into feces in a transmissible form and would spread by a fecal-oral route for deep and wide penetration into the general population.

Experimental African HEV infection in cynomolgus macaques (Macaca fascicularis)

Experimental infection with hepatitis E virus (HEV) from Africa has not been investigated. Our purpose was to study hepatitis E produced by HEV from Chad (North Africa) and to analyze the genetic sequence of the HEV obtained after animal passage. An HEV-containing fecal sample from Chad was intravenously inoculated in four cynomolgus macaques. When serum Alanine Amino Transferase (ALT) levels rose, open liver biopsy and bile aspiration were performed. In all the monkeys, an ALT rise occurred 25 to 32 days after inoculation and new anti-HEV was detected by Enzyme Immuno Assay (EIA). Hepatic histopathology was consistent with acute viral hepatitis. HEV was detected by polymerase chain reaction (PCR) in bile (3/4 animals) and feces (2/4 animals) and by imunoelectron microscopy (IEM) in the inoculum and one bile specimen. A genetic variant HEV was identified in one monkey. The Chad HEV produced hepatitis E with pathophysiologic and histopathologic findings similar to those observed with HEV from other geographic origins. A genomic variant HEV population was produced after one passage in a macaque.

Expression and self-assembly of empty virus-like particles of hepatitis E virus

Hepatitis E virus (HEV) is a pathogenic agent that causes fecally-orally transmitted acute hepatitis. The genome, a single-stranded positive-sense RNA, encodes three forward open reading frames (ORFs), in which an approximately 2-kb structural protein is located in the 3' end. To produce HEV-like particles the structural protein, with its N terminus truncated (amino acid residues 112 to 660 of ORF2), was expressed in insect Tn5 cells by a recombinant baculovirus. In addition to the primary translation product with a molecular mass of 58 kDa, a large amount of a further-processed molecule with a molecular mass of 50 kDa was generated and efficiently released into the culture medium. Electron microscopic observation of the culture medium revealed that the 50-kDa protein self-assembled to form empty virus-like particles (VLPs). The buoyant density of the VLPs in CsCl was 1.285 g/cm3 and their diameter was 23.7 nm, a little smaller than the 27 nm of native HEV particles secreted into the bile or stools of experimentally infected monkeys. The yield of the VLPs was 1 mg per 10(7) cells as a purified form. The particles possess antigenicity similar to that of authentic HEV particles and, consequently, they appear to be a good antigen for the sensitive detection of HEV-specific immunoglobulin G (IgG) and IgM antibodies. Furthermore, the VLP may be the most promising candidate yet for an HEV vaccine, owing to its potent immunogenicity.

Detection of hepatitis C virus RNA in bile

OBJECTIVES

The infectivity of bile in patients with hepatitis C virus (HCV) infection remains to be clarified. The purpose of this study was to document the detection of HCV-RNA in bile of patients with HCV infection.

METHODS

Bile and serum samples were tested for HCV RNA by a two-step polymerase chain reaction technique in 12 patients with HCV infection.

RESULTS

HCV-RNA was detected in the serum of all 12 patients, whereas 6 of 12 bile samples (50%) tested positive. Comparison of laboratory data between patients with and without HCV-RNA in bile demonstrated statistically higher serum total bilirubin among those with positive bile HCV RNA than those without, but other clinical and biochemical variables as well as hepatitis activity scores were comparable between the two groups.

CONCLUSIONS

Bile of HCV antibody-positive patients could be infectious.

Viral RNA in duodenal bile of cirrhotic patients with chronic hepatitis C

BACKGROUND

Hepatitis C virus (HCV) has been detected in blood, saliva, urine, semen, breast milk, and tears. To our knowledge, bile has not yet been investigated. We observed histologic immunoreactivity in bile with an antibody to c100 protein in four of five HCV-positive cirrhotic livers, but also in two HCV-negative controls owing to a focally present cross-reacting antigen.

METHODS

We collected duodenal bile from 13 cirrhotic patients during endoscopic evaluation of varices (10 HCV, three controls) and assayed for HCV by reverse transcriptase polymerase chain reaction.

RESULTS

Viral RNA was detected in the bile of 8 of 10 seropositive patients and in 0 of 3 seronegative controls.

CONCLUSION

Hepatitis C virus RNA and an antigen immunoreactive with anti-c100 protein are present in bile in a proportion of cirrhotic patients with chronic HCV. It remains to be determined whether the virus is intact or degenerate, and whether it is shed into bile from hepatocytes or is a contaminant from blood or other secretions.