Longer Poly(U) Stretches in the 3'UTR Are Essential for Replication of the Hepatitis C Virus Genotype 4a Clone in in vitro and in vivo

The 3′ untranslated region (UTR) of the hepatitis C virus (HCV) genome plays a significant role in replication including the poly(U) tract (You and Rice, 2008). Here we established an HCV clone that is infectious in vitro and in vivo, from an Egyptian patient with chronic HCV infection and hepatocellular carcinoma (HCC). First, we inoculated the patient plasma into a humanized chimeric mouse and passaged. We observed HCV genotype 4a propagation in the chimeric mouse sera at 1.7 × 10⁷ copies/mL after 6 weeks. Next, we cloned the entire HCV sequence from the HCV-infected chimeric mouse sera using RT-PCR, and 5′ and 3′ RACE methodologies. We obtained first a shorter clone (HCV-G4 KM short, GenBank: AB795432.1), which contained 9,545 nucleotides with 341 nucleotides of the 5′UTR and 177 nucleotides of the 3′UTR, and this was frequently obtained for unknown reasons. We also obtained a longer clone by dividing the HCV genome into three fragments and the poly (U) sequences. We obtained a longer 3′UTR sequence than that of the HCV-G4 KM short clone, which contained 9,617 nucleotides. This longer clone possessed a 3′-UTR of 249 nucleotides (HCV-G4 KM long, GenBank: AB795432.2), because of a 71-nucleotide longer poly (U) stretch. The HCV-G4-KM long clone, but not the HCV-G4-KM short clone, could establish infection in human hepatoma HuH-7 cells. HCV RNAs carrying a nanoluciferase (NL) reporter were also constructed and higher replication activity was observed with G4-KM long-NL in vitro. Next, both short and long RNAs were intra-hepatically injected into humanized chimeric mice. Viral propagation was only observed for the chimeric mouse injected with the HCV-G4 KM long RNA in the sera after 21 days (1.64 × 10⁶ copies/mL) and continued until 10 weeks post inoculation (wpi; 1.45–4.74 × 10⁷ copies/mL). Moreover, sequencing of the HCV genome in mouse sera at 6 wpi revealed the sequence of the HCV-G4-KM long clone. Thus, the in vitro and in vivo results of this study indicate that the sequence of the HCV-G4-KM long RNA is that of an infectious clone.

Serum and Urinary Interferon-Gamma-Inducible Protein 10 in Lupus Nephritis

BACKGROUND

Lupus nephritis is a serious manifestation of systemic lupus erythematosus (SLE). The objective of this study was to identify the sensitivity, specificity, and cut-off values of IP-10 in the serum and urine of patients with lupus nephritis compared to renal biopsy, albumin/creatinine ratio, and serum anti-dsDNA.

METHODS

Thirty female SLE patients were included. SLEDAI was calculated and blood and urine samples were collected. Patients were divided into 10 SLE patients with renal involvement (six active and four inactive), 10 active SLE, and 10 inactive SLE patients. Ten age-matched healthy (control) were included. Serum and urinary levels of IP-10 were measured by ELISA. Anti-dsDNA, urine albumin/creatinine ratio were performed.

RESULTS

Serum and urinary IP-10 in active SLE patients had significantly increased levels as compared to inactive SLE patients (P = 0.015, P = 0.033, respectively). However, there was no difference in serum and urinary levels between active renal and active non-renal patients. Albumin/creatinine ratio is a better marker in differentiating between lupus nephritis and SLE with no renal involvement. Any of serum and urinary IP-10, albumin/creatinine ratio, and anti-dsDNA did not correlate with the class of lupus nephritis in renal biopsy.

CONCLUSION

Urinary and serum IP-10 are useful markers of lupus activity, but not indicative of renal activity. Albumin/creatinine ratio is superior in identifying lupus nephritis and renal activity.

A serine palmitoyltransferase inhibitor blocks hepatitis C virus replication in human hepatocytes

BACKGROUND & AIMS

Host cell lipid rafts form a scaffold required for replication of hepatitis C virus (HCV). Serine palmitoyltransferases (SPTs) produce sphingolipids, which are essential components of the lipid rafts that associate with HCV nonstructural proteins. Prevention of the de novo synthesis of sphingolipids by an SPT inhibitor disrupts the HCV replication complex and thereby inhibits HCV replication. We investigated the ability of the SPT inhibitor NA808 to prevent HCV replication in cells and mice.

METHODS

We tested the ability of NA808 to inhibit SPT's enzymatic activity in FLR3-1 replicon cells. We used a replicon system to select for HCV variants that became resistant to NA808 at concentrations 4- to 6-fold the 50% inhibitory concentration, after 14 rounds of cell passage. We assessed the ability of NA808 or telaprevir to inhibit replication of HCV genotypes 1a, 1b, 2a, 3a, and 4a in mice with humanized livers (transplanted with human hepatocytes). NA808 was injected intravenously, with or without pegylated interferon alfa-2a and HCV polymerase and/or protease inhibitors.

RESULTS

NA808 prevented HCV replication via noncompetitive inhibition of SPT; no resistance mutations developed. NA808 prevented replication of all HCV genotypes tested in mice with humanized livers. Intravenous NA808 significantly reduced viral load in the mice and had synergistic effects with pegylated interferon alfa-2a and HCV polymerase and protease inhibitors.

CONCLUSIONS

The SPT inhibitor NA808 prevents replication of HCV genotypes 1a, 1b, 2a, 3a, and 4a in cultured hepatocytes and in mice with humanized livers. It might be developed for treatment of HCV infection or used in combination with pegylated interferon alfa-2a or HCV polymerase or protease inhibitors.

Genomic polymorphisms in 3β-hydroxysterol Δ24-reductase promoter sequences

It was recently reported by the present team that 3β-hydroxysterol Δ24-reductase (DHCR24) is induced by hepatitis C virus (HCV) infection. In addition, upregulation of DHCR24 impairs p53 activity. In human hepatoma HuH-7 cells, the degree of DHCR24 expression is higher than in normal hepatic cell lines (WRL68) at the transcriptional level. The genomic promoter sequence of DHCR24 was characterized and nucleotide substitutions were observed in HuH-7 cells at nucleotide numbers -1453 (G to A), -1420 (G to T), -488 (A to C) and -200 (G to C). The mutations of these sequences from HuH-7 cell types to WRL68 cell types suppressed DHCR24 gene promoter activity. The sequences were further characterized in hepatocytes from patient tissues. Four tissues from HCV-positive patients with cirrhosis or hepatocellular carcinoma (#1, 2, 3, 5) possessed HuH-7 cell type sequences. Interestingly, one patient with liver cirrhosis (#4) possessed WRL68 cell-type sequences; this patient had been infected with HCV and was HCV negative for 17 years after interferon therapy. Next, the effect of HCV infection on these polymorphisms was examined in humanized chimeric mouse liver and HuH-7 cells. The human hepatocytes possess WRL68 cell type and did not show the nucleotide substitution after HCV infection. The HCV-replicon was removed by interferon treatment and established the cured K4 cells. These cells possess HuH-7 cell type sequences. Thus, this study showed the genomic polymorphism in DHCR24 promoter is not directly influenced by HCV infection.

Impact of soil and groundwater corrosion on the Hierakonpolis Temple Town archaeological site, Wadi Abu Sufian, Idfu, Egypt

Hierakonpolis, Greek for City of the Hawk, nearly 25 km NW of Idfu (Egypt), is an important and extensive archaeological discovery covering a large area. Its richness in archaeological artifacts makes it a valuable site. It has a valid claim to be the first nation state, as indicated by the Palette of Narmer discovered in its main mound. Geological and hydrogeological investigations at the Hierakonpolis Temple Town site documented nearly a 4.0-m water table rise from as early as 1892 to the present. In addition to the rising water levels, the increase of both subsoil water salinity and humidity threatens and damages fragile carvings and paintings within tombs in Kingdom Hill, the foundation stability of the site, and the known and still to be discovered artifact that recent pottery finds dates at least 4,000 BCE. Representative rock and soil samples obtained from drilled cores in the study area were chosen for conducting detailed grain size and X-ray analysis, light and heavy mineral occurrences, distribution of moisture and total organic matter, and scanning electron microscopy investigations. Mineralogical analysis of clays indicated that the soil samples are composed of smectite/illite mixed layers with varying proportions of smectite to illite. Kaolinite is the second dominant clay constituent, besides occasional chlorite. Swelling of the clay portion of the soil, due to the presence of capillary groundwater, in contact with buried mudbrick walls expands and causes severe damage to important exposed and buried mudbrick structures, including the massive ancient "fort" believed to date from the Second Dynasty (from 2,890 to 2,686 BC). The "fort" is 1.0 km south of the Temple Town mounds near to confluence of Wadi Abu Sufian. Groundwater samples from the shallow aquifer close by the intersection of Wadi Abu Sufian and the Nile flood plain were analyzed for chemical composition and stable isotope ratios. The groundwater in the upper zone (subsoil water) within fine-grained Nile alluvium is characterized by high salinity which varies from 415 to 4,500 mg/L total dissolved solids. In contrast, most of the groundwater samples in the lower zone (Quaternary aquifer) are characterized by a low salinity in the order of 164-792 mg/L. Values of δD and δO(18) obtained from this deep (9-20 m) aquifer ranged from 16.98 to 19.87 ‰ and from 1.67 to 2.99 ‰, respectively. These values indicated that the Quaternary aquifer waters are recharged directly from recent Nile water. Subsoil water is very shallow in the area; it ranged from 0 to 2.6 m with a mean of 1.1 m within the main mound of the Hierakonpolis Temple Town site by 2003, in contrast to its more than 4.5-m depth in 1897. The exposure of subsoil water to increased evaporation is expected, with a consequent increase in the concentrations of dissolved solids and usually large proportions of chloride and sulfate. Artifacts recovered from the Temple Town site are becoming damaged and destroyed by crystallization processes caused by repeated wetting and drying of salt and the accumulation of new salts.

Alterations in neutrophil surface expression of L-selectin (CD62L) and soluble L-selectin (sL-selectin) in hemodialysis patients: relation to HCV

High levels of L-selectin (CD62L) are a strong indicator of endothelial dysfunction, and atherosclerosis. Atherosclerosis is the leading cause of mortality and morbidity in hemodialysis (HD) patients. Whether HCV infection (highly prevalent in HD patients and also associated with alterations in adhesion molecules) would affect the leukocytic expression and/or the soluble form of L-selectin in hemodialysis patients is unknown. Seventy-two HD patients, HCV-positive (n=48) and HCV-negative (n=24) and 10 normal control were studied. Blood samples were obtained just prior to the start of the dialysis session (predialysis) and at the end of 15 min. of dialysis (intradialysis). The following tests were performed on all patients: HCV-RNA by RT-nested PCR, quantitative determination of sL-selectin by ELISA and neutrophil surface expression of L-selectin (CD62L) by flowcytometry. Both CD62L and sL-selectin were found to be significantly higher in HD patients as compared to normal controls irrespective to HCV. Fifteen minutes after start of the dialysis session both CD62L and absolute neutrophil count decreased significantly [CD62L, p < 0.0001 (HCV-positive), p= 0.03 in (HCV-negative), [neutrophil count, p < 0.0001 each], while sL-selectin showed a significant increase [p = 0.004 (HCV-positive), p = 0.006 (HCV-negative)]. These changes were unrelated to HCV status. A significant increase in CD62L in HCV-positive patients compared to HCV-negative ones in both pre and intradialysis samples was noted (p = 0.007, p = 0.02 respectively). However, no difference was observed in either sL-selectin or absolute neutrophil count between the two groups in the two tested time points. In conclusions, the increased levels of neutrophil-expressed and soluble forms of L-selectin in HD patients, and the intradialysis increase in sL-selectin and decrease in CD62L and neutrophil count are unrelated to HCV viremia. The association between HCV positivity and neutrophil expression of pre andintradialysis L-selectin point to a possible role of HCV that needs further studies.

Molecular epidemiology of hepatitis B virus in the United Republic of Tanzania

In the United Republic of Tanzania, 457 voluntary blood donors were enrolled in hepatitis B virus (HBV) serological screening; 4.8% (22/457) carried HBsAg, 13.6% (3/22) of whom were HBeAg-positive. The mean age among HBeAg-negative carriers was 31 years. HBV DNA was detectable in 81.8% (18/22), the mean level was 3.67 (+/-1.77) log copies/ml. Genotype A was determined in 90.9% (20/22) and 18/20 were classified into subgenotype Aa (Asia/Africa). The basal core promoter, precore and partial core nucleotide sequences were analyzed in the 18 strains; T1809/T1812 ("Kozak" sequence) and A/T1888 (encapsidation signal) variants were identified in 100% and 78%, respectively. The complete genome sequencing for one of the Tanzanian strains revealed no recombination. In conclusion, HBV seroprevalence is high among general population in Tanzania, and the HBV/Aa-infection is predominant. The indicated tendency to early HBeAg seroconversion and declining of the viral load should be confirmed further in case-control studies.

Distribution of HBV genotypes among HBV carriers in Benin:phylogenetic analysis and virological characteristics of HBV genotype E

AIM: To determine the distribution of Hepatitis B virus (HBV) genotypes in Benin, and to clarify the virological characteristics of the dominant genotype.

METHODS: Among 500 blood donors in Benin, 21 HBsAg-positive donors were enrolled in the study. HBV genotypes were determined by enzyme immunoassay and restriction fragment length polymorphism. Complete genome sequences were determined by PCR and direct sequencing.

RESULTS: HBV genotype E (HBV/E) was detected in 20/21 (95.2%), and HBV/A in 1/21 (4.8%). From the age-specific prevalence of HBeAg to anti-HBe seroconversion (SC) in 19 HBV/E subjects, SC was estimated to occur frequently in late teens in HBV/E. The comparison of four complete HBV/E genomes from HBeAg-positive subjects in this study and five HBV/E sequences recruited from the database revealed that HBV/E was distributed throughout West Africa with very low genetic diversity (nucleotide homology 96.7-99.2%). Based on the sequences in the basic core promoter (BCP) to precore region of the nine HBV/E isolates compared to those of the other genotypes, a nucleotide substitution in the BCP, G1757A, was observed in HBV/E.

CONCLUSION: HBV/E is predominant in the Republic of Benin, and SC is estimated to occur in late teens in HBV/E. The specific nucleotide substitution G1757A in BCP, which might influence the virological characteristics, is observed in HBV/E.

Diagnosis of Ornithobacterium rhinotracheale infection in chickens by ELISA

Specific Ornithobacterium rhinotracheale (ORT) antibodies were determined in serum samples of 24 clinically infected broiler flocks of different ages (1-42 d) and 11 broiler-breeding flocks (at ages between 26-56 w) by ELISA. Two commercially available kits were separately assessed. The BioCheck ELISA kit was used for testing 363 serum samples representing 12 broiler flocks, where 74 samples (20.3 %) were found to be positive and 49 (13.5 %) were suspected. The IDEXX ELISA kit was used for testing 148 serum samples representing different 12 broiler flocks, where 115 samples (77.7 %) were positive. Testing of additional 70 serum samples from 5 broiler- breeder flocks, associated with drop in egg production (1-4.5 %) at different ages, by BioCheck ELISA kit revealed that 78.5 % of the samples were positive and 21.4% were suspected. On the other hand, 338 serum samples representing 6 broiler-breeder flocks, associated also with egg drop, showed a 84.6 % rate of positive reaction, when tested by IDEXX ELISA kit. Positive serology correlated well with the clinical manifestations and isolation of the organism, which substantiates the reliability of the used kits in diagnosis of the disease.

Role of a sentinel surveillance system in the context of global surveillance of infectious diseases

In some nation states, sustained integrated global epidemiological surveillance has been weakened as a result of political unrest, disinterest, and a poorly developed infrastructure due to rapidly increasing global inequality. The emergence of severe acute respiratory syndrome has shown vividly the importance of sensitive worldwide surveillance. The Agency for Cooperation in International Health, a Japanese non-governmental organisation, has developed on a voluntary basis a sentinel surveillance system for selected target infectious diseases, covering South America, Africa, and Asia. The system has uncovered unreported infectious diseases of international importance including cholera, plague, and influenza; current trends of acute flaccid paralysis surveillance in polio eradication; and prevalence of HIV, syphilis, hepatitis B, and hepatitis C in individual areas covered by the sentinels. Despite a limited geographical coverage, the system seems to supplement disease information being obtained by global surveillance. Further development of this sentinel surveillance system would be desirable to contribute to current global surveillance efforts, for which, needless to say, national surveillance and alert system takes principal responsibility.

Distribution of hepatitis B virus (HBV) genotypes among HBV carriers in the Cote d'Ivoire: complete genome sequence and phylogenetic relatedness of HBV genotype E

The characteristics of hepatitis B virus (HBV) genotype E are not well known because only a few studies have been carried out by complete genome analysis. The aim of this study was to elucidate the distribution of HBV genotypes in Cote d'Ivoire, and to clarify the genotype-related characteristics of genotype E. The distribution of HBV genotypes among 48 HBV carriers in Cote d'Ivoire was determined using serological and genetic methods. The characteristics of genotype E were evaluated by complete genome sequences, and further investigations of small S gene, basic core promoter (BCP) mutation, and precore mutation were undertaken. HBV genotype distribution among the 48 carriers was 6.3% for genotype A, 6.3% for genotype D, and 87.4% for genotype E. Complete genomes of two genotype E strains were sequenced, and found to have 98.2% to 99.2% homology at the nucleotide level when compared with genotype E strains reported previously. In 24 genotype E carriers, the precore mutation was detected in 75% of the patients without HBeAg, in contrast to only 25% of the patients with HBeAg (P < 0.05). All 24 strains have T at nucleotide 1858 in the precore region. In contrast, BCP double mutation was detected in 17% of the patients with HBeAg, and 33% of the patients without HBeAg. These results indicated as the following: (1) genotypes A, D, and E of HBV exist in Cote d'Ivoire and genotype E is the most prevalent; (2) genotype E spread with low genetic diversity over the complete genome in West Africa; (3) HBV precore and/or BCP double variants were common among the patients with genotype E infections.

The epidemiology of schistosomiasis in Egypt: Ismailia governorate

A multi-stage stratified sample of 12,515 individuals from 1,941 households in 42 villages in the Ismailia governorate of Egypt were surveyed for schistosomal infection. A subset of 2,390 subjects were surveyed for morbidity by physical and ultrasonographic examination. The prevalence of Schistosoma mansoni infection in rural Ismailia was 42.9% and the geometric mean egg count (GMEC) was 93.3 eggs/gram of stool, with considerable variability between communities. Prevalence and intensity peaked in the 20-30-year-old age group and was higher in males than in females. Prevalence and intensity of S. haematobium was very low: 1.8% and 3.5 ova/10 ml of urine GMEC, respectively. Canal water exposure risk factors for S. mansoni infection were males bathing (odds ratio [OR] = 2.2), females washing clothes (OR = 1.9), and children playing or swimming (OR = 2.3). Presence of in-house piped water supply and latrine lowered infection rates (P < 0.001 and P = 0.002, respectively). Histories of S. mansoni infection (OR = 1.6) or treatment (OR = 1.5) and blood in feces (OR = 3.5) were associated with infection. Hepatomegaly (16.0%) was more frequently detected than splenomegaly (3.6%) by physical examination, with both being more frequent in older age groups. Splenomegaly, but not hepatomegaly, was associated with presence of S. mansoni ova in stools (OR = 1.4) and the community burden of infection (P = 0.02). Ultrasonographically detected hepatomegaly, splenomegaly, and periportal fibrosis (PPF) were detected in 43.0%, 17.4%, and 39.7% of the subjects, respectively. The higher grades of PPF were rare. Ultrasonographically detected splenomegaly, not hepatomegaly, was associated with S. mansoni infection, community burden of infection, and PPF. Risk factors for PPF were the same as for S. mansoni infection. There was a marginal association of PPF with infection and none (P = 0.33) with the intensity of infection in individuals or in the community. We conclude that in rural Ismailia, S. haematobium infection is rare but the prevalence and intensity of infection with S. mansoni is high. The risk of infection is associated with environmentally detected factors and behaviors. Hepatosplenic morbidity attributable to S. mansoni infection is low, presumably because of the favorable effect of wide application of praziquantel therapy.