Current management strategies for hepatitis B in the elderly

Inpatient Cost Burdens of Treating Chronic Hepatitis B in US Hospitals: A Weighted Analysis of a National Database

BACKGROUND AND AIMS

This study evaluates the cost burdens of inpatient care for chronic hepatitis B (CHB). We aimed to stratify the patients based on the presence of cirrhosis and conduct subgroup analyses on patient demographics and medical characteristics.

METHODS

The 2016-2019 National Inpatient Sample was used to select individuals diagnosed with CHB. The weighted charge estimates were derived and converted to admission costs, adjusting for inflation to the year 2016, and presented in United States Dollars. These adjusted values were stratified using select patient variables. To assess the goodness-of-fit for each trend, we graphed the data across the respective years, expressed in a chronological sequence with format (R2, p-value). Analysis of CHB patients was carried out in three groups: the composite CHB population, the subset of patients with cirrhosis, and the subset of patients without cirrhosis.

RESULTS

From 2016 to 2019, the total costs of hospitalizations in CHB patients were $603.82, $737.92, $758.29, and $809.01 million dollars from 2016 to 2019, respectively. We did not observe significant cost trends in the composite CHB population or in the cirrhosis and non-cirrhosis cohorts. However, we did find rising costs associated with age older than 65 (0.97, 0.02), white race (0.98, 0.01), Hispanic ethnicity (1.00, 0.001), and Medicare coverage (0.95, 0.02), the significance of which persisted regardless of the presence of cirrhosis. Additionally, inpatients without cirrhosis who had comorbid metabolic dysfunction-associated steatotic liver disease (MASLD) were also observed to have rising costs (0.96, 0.02).

CONCLUSIONS

We did not find a significant increase in overall costs with CHB inpatients, regardless of the presence of cirrhosis. However, certain groups are more susceptible to escalating costs. Therefore, increased screening and nuanced vaccination planning must be optimized in order to prevent and mitigate these growing cost burdens on vulnerable populations.

HIV, aging, and adherence: an update and future directions

PURPOSE OF REVIEW

To highlight recent data on antiretroviral adherence in older people living with HIV (PLWH), describe the most relevant pharmacokinetic antiretroviral studies, and identify critical research gaps in this population.

RECENT FINDINGS

Overall, studies have found that older PLWH are more likely to be adherent to antiretroviral therapy (ART). Although multiple methods to measure adherence are available (self-report, pharmacy refills, electronic device monitors, drug concentrations), there is currently no 'gold standard' adherence measure or sufficient evidence to suggest a preferred method in older patients. Recently, studies evaluating antiretroviral concentrations in hair and dried blood spots in older patients identified no major differences when compared with younger individuals. Similarly, although pharmacokinetic studies in older PLWH are scarce, most data reveal no significant pharmacokinetic differences in the aging population. Furthermore, no specific guidelines or treatment recommendations regarding ART dose modification or long-term toxicity in aging PLWH are available, mostly because of the exclusion of this population in clinical trials.

SUMMARY

How aging influences adherence and pharmacokinetics remains poorly understood. As the population of older PLWH increases, research focusing on adherence, toxicity, drug--drug interactions, and the influence of comorbidities is needed.

An update of the incidence of fulminant hepatitis due to viral agents during pregnancy

Fulminant hepatitis in pregnant women is one of the major public health issues and remains a challenging clinical problem with extremely high maternal and fetal morbidity and mortality, which, in parallel, viral factors are the most common cause of hepatic disorders and dysfunction during pregnancy that may lead to fulminant hepatic with a fast progression. Therefore, this review helps to inform clinicians about the current status of the incidence of fulminant hepatitis due to viral agents during pregnancy.

Short-term efficacy of treating hepatitis B virus-related acute-on-chronic liver failure based on cold pattern differentiation with hot herbs: A randomized controlled trial

OBJECTIVE

To evaluate the clinical efficacy and safety of Yinchen Zhufu Decoction (, YCZFD) in the treatment of acute-on-chronic liver failure caused by hepatitis B virus (HBV-ACLF) with cold pattern in Chinese medicine (CM).

METHODS

This is a multi-center randomized controlled trial of integrative treatment of CM and Western medicine (WM) for the management of HBV-ACLF patients. A total of 200 HBV-ACLF patients with cold pattern were equally randomly assigned to receive YCZFD and WM (integrative treatment) or WM conventional therapy alone respectively for 4 weeks. The primary end point was the mortality for HBV-ACLF patients. Secondary outcome measures included Model for End-Stage Liver disease (MELD) score, liver biochemical function, coagulation function and complications. Adverse events during treatment were reported.

RESULTS

The mortality was decreased 14.28% in the integrative treatment group compared with WM group (χ(2) =6.156, P=0.013). The integrative treatment was found to signifificantly improve the MELD score (t=2.353, P=0.020). There were statistically signifificant differences in aspartate transaminase, total bilirubin, indirect bilirubin, direct bilirubin and prothrombin time between the two groups (P<0.05 or P<0.01). The complications of ascites (χ(2)=9.033, P=0.003) and spontaneous bacteria peritonitis (χ(2)=4.194, P=0.041) were improved signifificantly in the integrative treatment group. No serious adverse event was reported.

CONCLUSIONS

The integrative treatment of CM and WM was effective and safe for HBV-ACLF patients with cold pattern in CM. The Chinese therapeutic principle "treating cold pattern with hot herbs" remains valuable to the clinical therapy. (Trial registration No. ChiCTR-TRC-10000766).

Comparison of efficacy and renal safety of telbivudine and entecavir in treatment-naive elderly patients with chronic hepatitis B

BACKGROUND

Data comparing the clinical outcomes of telbivudine (LdT) and entecavir (ETV) in elderly patients with chronic hepatitis B are limited.

GOALS

The aim of the present study was to compare the efficacy and renal safety of LdT and ETV in treatment-naive elderly (≥ 60 years) patients with chronic hepatitis B.

METHODS

A total of 33 patients treated with LdT were consecutively enrolled in the study. Each patient was matched on the basis of age, sex, and baseline hepatitis B virus (HBV) DNA levels with three to four randomly selected controls treated with ETV.

RESULTS

Clinical characteristics were comparable between the two groups. Higher cumulative HBeAg-seroconversion rates were observed in the LdT group than in the ETV group after 2 years (50 vs. 20%) and 3 years (50 vs. 26.67%) of treatment (all P<0.0001). Virological response rate at week 24 was significantly lower in the LdT group than it was in the ETV group (54.55 vs. 70.87%, P<0.0001), but no significant difference was noted in long-term cumulative rates of undetectable HBV DNA levels between the two groups (P=0.562). Virological breakthrough occurred in six (18.18%) LdT patients, with no such cases reported in the ETV group (P<0.0001). Antiviral resistance was strongly associated with LdT use and the absence of undetectable HBV DNA at weeks 12 and 24 (P<0.0001). During the study, significant improvement was observed in the estimated glomerular filtration rate and model for end-stage liver disease score in LdT versus ETV group.

CONCLUSION

LdT has a lower clinical efficacy for viral suppression and a higher risk of antiviral resistance than does ETV. However, LdT resulted in higher HBeAg-seroconversion rates and better renoprotective effects than did ETV.

HMGB1/RAGE induces IL-17 expression to exaggerate inflammation in peripheral blood cells of hepatitis B patients

BACKGROUND

Hepatitis B (HB) is an infectious disease with unfavorable consequence for patients and involved in chronic inflammation of liver. The present study aimed to investigate whether High-mobility group protein B (HMGB)1/receptor for advanced glycation end products (RAGE) aggravates inflammation enhancing the expression of interleukin (IL)-17.

METHODS

Mild and severe HB liver tissue and peripheral blood samples were obtained intra-operatively. Histological analysis of the livers was performed by immunohistochemistry. IL-1β and IL-6 of liver tissue were detected by confocal microscopy staining. Relative mRNA expression was measured by real-time PCR and protein levels were measured by enzyme-linked immunosorbent assay.

RESULTS

HMGB1, RAGE and IL-17 expression is increased in liver of HB patients with acute on chronic liver failure (ACLF) compared to healthy controls. HMGB1 treatment induced inflammatory cytokines including IL-17 in peripheral blood cells of HB patients. IL-17 also induced the expression of RAGE and IL-1β in peripheral blood cells of HB patients with ACLF. On the other hands, the inhibitory factor of p38 and nuclear factor-kappa B reduced the expression of RAGE and IL-1β in peripheral blood cells HB patients with ACLF.

CONCLUSIONS

HMGB1, RAGE and IL-17 expression is increased in liver of severe HB patients. HMGB1 and RAGE interaction may contribute to the inflammation of liver enhancing the expression of IL-17, which can be possibly restored through the decline of the HMGB1/RAGE axis.

Effectiveness and safety of double-balloon catheter versus intra-amniotic injection of ethacridine lactate for termination of second trimester pregnancy in patients with liver dysfunction

Severe liver dysfunction in pregnancy (SLDP) is rare but serious complications with high mortality rate. This study compared the effectiveness and safety of double-balloon catheter versus intra-amniotic injection of ethacridine lactate for the termination of second trimester pregnancy in patients with SLD. A total of 55 patients with indications of labor induction were enrolled and analyzed by retrospective control analysis method. Twenty-three cases adopted Cook double balloon dilation as Cook group, and 32 cases received intra-amniotic injection of ethacridine lactate as EL group. The primary outcome was evaluated by successful abortion rate and the difference in the induction-to-abortion interval. Secondary outcomes included liver function recovery and the frequency of adverse events. Both Cook and EL regimens were effective, with successful abortion rate of 87.0% and 93.8%, respectively (P=0.639). The induction-to-delivery interval was similar between Cook group and EL group (38.1 ± 21.5 vs. 41.3 ± 17.4, P=0.543). The liver disease status was more severe in Cook group than in EL group, but it did not show any significant difference after pregnancy termination between the two groups and the improvement rate also did not show any significant difference. Both treatments were safe and there was no significant difference in bleeding and cervical laceration adverse events between the two groups. Our study firstly compared double-balloon catheter and ethacridine lactate for the induction of labor in women with SLD during second trimester pregnancy.

Prognostic value of the neutrophil-to-lymphocyte ratio in patients with acute-on-chronic liver failure

OBJECTIVES

The neutrophil-to-lymphocyte ratio (NLR) is a novel inflammation index that has been shown to independently predict poor clinical outcomes. We aimed to evaluate the role of NLR in the prediction of 3-month mortality in patients with acute-on-chronic liver failure (AoCLF).

METHODS

One hundred and twenty-seven patients, including 46 patients with chronic hepatitis B (CHB), 81 with AoCLF and 58 healthy controls (HCs), were enrolled in the study. All patients were followed up for 4 months. The primary end-point was in-hospital mortality at the end of 90 days. A blood sample was collected for all subjects at admission to examine liver function, renal function, international normalised ratio, C-reactive protein and neutrophil and lymphocyte counts, and NLRs were calculated. A total of six clinical chemistry and biochemical variables were analysed for potential associations with outcomes using Cox proportional hazards and multiple regression models.

RESULTS

Acute-on-chronic liver failure patients had significantly higher NLRs on admission compared with HCs and CHB patients (all p = 0.001). Patients with elevated NLRs were associated with increased severity of liver disease and 3-month mortality rates. According to multivariate analysis, only NLR was an independent predictor for mortality (p = 0.025).

CONCLUSIONS

The NLR measured at admission can serve as an independent predictor for 3-month mortality rate in AoCLF patients.

Clinical pharmacokinetics of antiretroviral drugs in older persons

INTRODUCTION

Combination antiretroviral therapy has enabled HIV-infected persons to reach older ages in high numbers. Hepatic and renal changes that normally occur with advancing age occur earlier and with higher incidence in HIV-infected individuals. A limited number of prospective controlled studies have demonstrated small reductions (17 to 41%) in lopinavir, atazanavir and lamivudine clearance in older versus younger adults. A much larger number of retrospective studies in adults (age range ∼ 20 to 60 years), including all antiretroviral drugs, have evaluated age as a covariate for pharmacokinetics. Most studies did not detect substantial associations between drug exposures and age.

AREAS COVERED

This review summarizes antiretroviral drug pharmacokinetics in older persons. The authors review articles from PubMed (search terms: elderly, antiretroviral, pharmacokinetics) in addition to the bibliographies of those selected.

EXPERT OPINION

The evidence to date does not support major pharmacokinetic changes in adults between ∼ 20 and 60 years of age. However, additional prospective, well-controlled studies are needed in more persons > 60 years, including those with frailty and comorbidities, with assessment of unbound drug clearance, and incorporation of adherence, pharmacogenetics and concomitant medications. Until then, guidelines for drug-drug interactions and dosing in renal and hepatic impairment should be followed in older HIV-infected individuals.

Different models in predicting the short-term prognosis of patients with hepatitis B virus-related acute-on-chronic liver failure

BACKGROUND AND AIMS

Effective assessing the prognosis of patients with end-stage liver disease is always challenging. This study aimed to investigate the accuracy of different models in predicting short-term prognosis of patients with hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF).

MATERIAL AND METHODS

We retrospectively evaluated survival of a cohort of patients with at least 3-month follow up. The receiver-operating-characteristic curves (ROC) were drawn for Child-Turcotte-Pugh (CTP) classification, King's College Hospital (KCH) criteria, model for end-stage liver disease (MELD), MELD combined with serum sodium (Na) concentration (MELDNa), integrated MELD (iMELD) and logistic regression model (LRM).

RESULTS

Of the 273 eligible patients, 152 patients (55.7%) died within 3-month follow up. In cirrhotic patients (n = 101), the AUCs of LRM (0.851), MELDNa (0.849), iMELD (0.845) and MELD (0.840) were all significantly higher than those of KCH criteria (0.642) and CTP (0.625) (all p < 0.05), while the differences among LRM, MELD, MELDNa and iMELD were not significant, and the most predictive cutoff value was 0.5176 for LRM, 30 for MELDNa, 47.87 for iMELD and 29 for MELD, respectively. In non-cirrhotic patients (n = 172), the AUC of LRM (0.897) was significantly higher than that of MELDNa (0.776), iMELD (0.768), MELD (0.758), KCH criteria (0.647) and CTP (0.629), respectively (all p < 0.05), and the most predictive cutoff value for LRM was -0.3264.

CONCLUSIONS

LRM, MELD, MELDNa and iMELD are with similar accuracy in predicting the shortterm prognosis of HBV-ACLF patients with liver cirrhosis, while LRM is superior to MELD, MELDNa and iMELD in predicting the short-term prognosis of HBV-ACLF patients without liver cirrhosis.

Survival and prognostic factors in hepatitis B virus-related acute-on-chronic liver failure

AIM

To investigate the survival rates and prognostic factors in patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF).

METHODS

Clinical data in hospitalized patients with HBV-ACLF admitted from 2006 to 2009 were retrospectively analyzed. Their general conditions and survival were analyzed by survival analysis and Cox regression analysis.

RESULTS

A total of 190 patients were included in this study. The overall 1-year survival rate was 57.6%. Patients not treated with antiviral drugs had a significantly higher mortality [relative risk (RR) = 0.609, P = 0.014]. The highest risk of death in patients with ACLF was associated with hepatorenal syndrome (HRS) (RR = 2.084, P =0.026), while other significant factors were electrolyte disturbances (RR = 2.062, P = 0.010), and hepatic encephalopathy (HE) (RR = 1.879, P < 0.001).

CONCLUSION

Antiviral therapy has a strong effect on the prognosis of the patients with HBV-ACLF by improving their 1-year survival rate. HRS, electrolyte disturbances, and HE also affect patient survival.

Lamivudine in late pregnancy to interrupt in utero transmission of hepatitis B virus: a systematic review and meta-analysis

OBJECTIVES

To evaluate efficacy of lamivudine in reducing in utero transmission of hepatitis B virus (HBV).

DATA SOURCES

A database was constructed from Medline, EMBASE, Cochrane Library, National Science Digital Library, China Biological Medicine Database, and through contact with experts in the field from January 1990 to October 2009.

METHODS OF STUDY SELECTION

We used the Jadad score and Cochrane Collaboration's tool for assessing risk of bias.

TABULATION, INTEGRATION, AND RESULTS

We abstracted data regarding HBV intrauterine infection, mother-to-child transmission, maternal HBV DNA level, treatment methods, and adverse effects. All newborns followed joint immune prophylaxis schedule of hepatitis B vaccine and hepatitis B immunoglobulin after delivery. The Mantel-Haenszel random-effects model was employed for all analyses using odds ratio (OR) and 95% confidence interval. Compared with the no-treatment group or placebo group, newborns in the lamivudine group had a 10.7–23.7% lower incidence of intrauterine infection, indicated by newborn hepatitis B surface antigen (0.38,0.15–0.94, six randomized controlled trials [RCTs], P5.04) and HBV DNA (0.22, 0.12–0.40, four RCTs, P,.001) seropositivity, and a 12.7–33.2% lower mother-to child transmission rate at 9–12 months, indicated by infant hepatitis B surface antigen (0.31, 0.15–0.63, five RCTs, P,.01) and HBV DNA (0.20, 0.10–0.39, two RCTs,P,.001) seropositivity [corrected].No significant higher adverse effects or complications in pregnancy were observed.

CONCLUSION

Lamivudine in HBV carrier-mothers with high degree of infectiousness in late pregnancy effectively prevented HBV intrauterine infection and mother-to-child transmission.

Prediction of the prognosis of patients with acute-on-chronic hepatitis B liver failure using the model for end-stage liver disease scoring system and a novel logistic regression model

The objective of this study was to determine the predictive value of the model for end-stage liver disease (MELD) scoring system in patients with acute-on-chronic hepatitis B liver failure (ACLF-HBV), and to establish a new model for predicting the prognosis of ACLF-HBV. A total of 204 adult patients with ACLF-HBV were retrospectively recruited between July 1, 2002 and December 31, 2004. The MELD scores were calculated according to the widely accepted formula. The 3-month mortality was calculated. The validity of the MELD model was determined by means of the concordance (c) statistic. Clinical data and biochemical values were included in the multivariate logistic regression analysis based on which the regression model for predicting prognosis was established. The receiver-operating characteristic curves were drawn for the MELD scoring system and the new regression model and the areas under the curves (AUC) were compared by the z-test. The 3-month mortality rate was 57.8%. The mean MELD score for the patients who died was significantly greater than those who survived beyond 3 months (28.7 vs 22.4, P = 0.003). The concordance (c) statistic (equivalent to the AUC) for the MELD scoring system predicting 3-month mortality was 0.709 (SE = 0.036, P < 0.001, 95% confidence interval 0.638-0.780). The independent factors predicting prognosis were hepatorenal syndrome (P < 0.001), liver cirrhosis (P = 0.009), HBeAg (P = 0.013), albumin (P = 0.028) and prothrombin activity (P = 0.011) as identified in multivariate logistic regression analysis. The regression model that was constructed by the logistic regression analysis produced a greater prognostic value (c = 0.891) than the MELD scoring system (z = 4.333, P < 0.001). The MELD scoring system is a promising and useful predictor for 3-month mortality of ACLF-HBV patients. Hepatorenal syndrome, liver cirrhosis, HBeAg, albumin and prothrombin activity are independent factors affecting the 3-month mortality. The newly established logistic regression model appears to be superior to the MELD scoring system in predicting 3-month mortality in patients with ACLF-HBV.

Inhibition of hepatitis B virus by an aqueous extract of Agrimonia eupatoria L

Inhibition of HBsAg release against hepatitis B virus (HBV) was investigated in an aqueous extract prepared from the aerial parts (stems and leaves) of Agrimonia eupatoria. The inhibitory effect on HBsAg secretion was footed using aqueous extracts of Agrimonia eupatoria at four different temperatures (37 degrees C 45 degrees C, 55 degrees C and 60 degrees C), and the extract prepared at 60 degrees C was found to have the greatest effect. The inhibitory activity of Agrimonia eupatoria extracts on HBsAg secretion varied over the growing season and was the highest at mid-July. This inhibitory activity was also shown with the aqueous extracts of two other species of the genus Agrimonia: A. pilosa and A. coreana pilosella. These results suggest that some plants of the genus Agrimonia contain potential antiviral activity against HBV.

Clinical characteristics of fulminant hepatitis in pregnancy

AIM: To investigate the clinical characteristics of fulminant hepatitis in pregnancy.

METHODS: We compared and analyzed the etiology, clinical characteristics, and laboratory examinations of 25 cases of fulminant hepatitis in pregnancy and 30 cases of fulminant hepatitis not in pregnancy.

RESULTS: HBV infection and chronic fulminant hepatitis were most common both in the pregnant and in the non-pregnant groups. Jaundice, digestive tract symptoms, increase of bilirubin and thrombinogen activity were the main manifestations. The incidence of hepatic encephalopathy (HE) and hepato-renal syndrome (HRS) was significantly different between the two groups. The incidence of preterm labor, dead fetus and neonatal asphyxia was high.

CONCLUSION: Fulminant hepatitis is likely to occur in late pregnancy with more severe complications, which significantly influences maternity, perinatal fetus, and newborn.

Analyses of prognostic indices of chronic liver failure caused by hepatitis virus

AIM: To analyze the related indices about the prognoses of chronic liver failure caused by hepatitis virus.

METHODS: Retrospectively reviewed 320 cases of chronic liver failure caused by hepatitis viruses. An improved group and an ineffective group (IG) were made to compare and analyze their clinical manifestations, laboratory examination indices and complications. Logistic regression was also carried out.

RESULTS: There were significant differences (P<0.05) between the improved group and the IG upon such indices as age, bilirubin, prothrombin time, albumin, alpha fetoprotein, the size of liver and complications (P<0.05). The regression formula was as follows: P = 1/(1+e^-y) (y = 1.7262-0.0948X₁+2.9846X₂+0.6992X₃+1.6019X₄+ 2.0398X₅). (Note: X₁-Prothrombin activity; X₂-digestive tract hemorrhage; X₃-hepatic encephalopathy; X₄-hepatorenal syndrome; X₅-pulmonary infection.).

CONCLUSION: Laboratory examination such as bilirubin, prothrombin time and alpha fetoprotein can be regarded as indices of the prognoses of chronic liver failure caused by hepatitis. Moreover, the regression equation can evaluate prognoses more comprehensively and direct our treatments.

Prospective study of response to interferon α-2b in chronic hepatitis B

AIM

To prospectively evaluate the response to interferon α-2b (IFN) in chronic hepatitis B.

METHODS

We enrolled a total number of 32 patients with CHB for the study. The patients received 6 million units of IFNα-2b subcutaneously thrice a weak for 3 months and also a follow-up for 6 months. Liver biopsies were obtained in 16 patients with CHB before and after treatment.

RESULTS

The complete response rate, partial response rate and non-response rate were 3.1%, 37.5% and 59.4%, respectively. The overall response rate was 40.6% (13/32) at the end of treatment. The overall response rate was 50.0% (16/32) at the end of follow-up.

CONCLUSION

Interferon-α had lasting antiviral effects in chronic hepatitis B. Some of the patients non-responsive to antiviral therapy acquired benefits from interferon-α treatment.

Lethiferous effects of a recombinant vector carrying thymidine kinase suicide gene on 2.2.15 cells via a self-modulating mechanism

AIM: To determine the lethiferous effects of a recombinant vector carrying thymidine kinase (TK) suicide gene on 2.2.15 cells and the possible self-modulating mechanism.

METHODS: A self-modulated expressive plasmid pcDNA3-SCITK was constructed by inserting the fragments carrying hepatitis B virus antisense-S (HBV-anti-S) gene, hepatitis C virus core (HCV-C) gene, internal ribosome entry site (IRES) element of HCV and TK gene into the eukaryotic vector pcDNA3, in which the expression of TK suicide gene was controlled by the HBV S gene transcription. 2.2.15 cells that carry the full HBV genome and stably express series of HBV antigen were transfected with pcDNA₃-SCITK or vector pcDNA₃-SCI which was used as the mock plasmid. The HepG2 cells transfected with pcDNA₃-SCITK were functioned as the negative control. All the transfected cells were incubated in DMEM medium supplemented with 10 μg/mL. of ganciclovir (GCV). The HBsAg levels in the supernatant of cell culture were detected by ELISA on the 1^st, 3^rd and 6^th day post-transfection. Meanwhile, the morphology of tranfected cells was recorded by the photograph and the survival cell ratio was assessed by the trypan blue exclusion test on the 6^th day post-transfection.

RESULTS: The structural accuracy of pcDNA₃-SCITK was confirmed by restriction endonuclease digestion, PCR with specific primers and DNA sequencing. The HBsAg levels in the supernatant of transfected 2.2.15 cell culture were significantly decreased on the 6^th day post-transfection as compared with that of the mock control (P < 0.05). The lethiferous effect of pcDNA₃-SCITK expression on 2.2.15 cells was initially noted on the 3^rd day after transfection and aggravated on the 6^th day post transfection, in which the majority of transfected 2.2.15 cells were observed shrunken, round in shape and even dead. With assessment by the trypan blue exclusion test, the survival cell ratio on the 6^th day post transfection was 95% in the negative control and only 11% in the experimental group.

CONCLUSION: The results indicate that suicide gene expression of pcDNA₃-SCITK can only respond to HBV-S gene transcription, which may be potentially useful in the treatment of HBV infection and its related liver malignancies.

Interruption of HBV intrauterine transmission: A clinical study

AIM: To investigate the effect of hepatitis B virus (HBV) specific immunoglobin (HBIG) and lamivudine on HBV intrauterine transmission in HBsAg positive pregnant women.

METHODS: Each subject in the HBIG group (56 cases) was given 200 IU HBIG intramuscularly (im.) every 4 wk from 28-week (wk) of gestation, while each subject in the lamivudine group (43 cases) received 100 mg lamivudine orally (po.) every day from 28-wk of gestation until the 30^th day after labor. Subjects in the control group (52 cases) received no specific treatment. Blood specimens were tested for HBsAg, HBeAg, and HBV-DNA in all maternities at 28-wk of gestation, before delivery, and in their newborns 24 h before the administration of immune prophylaxis.

RESULTS: Reductions of HBV DNA in both treatments were significant (P < 0.05). The rate of neonatal intrauterine HBV infection was significantly lower in HBIG group (16.1%) and lamivudine group (16.3%) compared with control group (32.7%) (P < 0.05), but there was no significant difference between HBIG group and lamivudine group (P > 0.05). No side effects were found in all the pregnant women or their newborns.

CONCLUSION: The risk of HBV intrauterine infection can be effectively reduced by administration of HBIG or Lamivudine in the 3^rd trimester of HBsAg positive pregnant women.

Cloning of HBsAg-encoded genes in different vectors and their expression in eukaryotic cells

AIM: To compare the efficiency of different plasmids as DNA vectors by cloning three HBsAg-encoded genes into two eukaryotic expression vectors, pRc/CMV and pSG5UTPL/Flag, and to express HBsAg S, MS, and LS proteins in SP2/0 cells, and to establish monoclone SP2/0 cell strains that are capable of expressing S or S2S proteins stably.

METHODS: Segments of S, preS2-S, preS1-preS2-S genes of Hepatitis B virus were amplified by routine PCR and preS1-S fragment was amplified by Over-Lap Extension PCR. The amplified segments were cleaved with restricted endonuclease Hind III/Not I followed by ligation with pRc/CMV, or BamH I/EcoR I followed by ligation with pSG5UTPL/Flag. After the plasmid vectors were cleaved with the correspond enzymes, the amplified segments were inserted into pRc/CMV or pSG5UTPL/Flag plasmid vectors with T4 DNA ligase. KOZAK sequence was added before the initial ATG code of each fragment using specific primer. The inserted segments in the recombinant plasmids were sequenced after subcloning. BALB/c mice myeloma cells (SP2/0 cell line) were transfected with the recombinant plasmids. The expressions of the different recombinants were Compared by Western-blot, using a monoclonal anti-HBs antibody as the primary antibody and peroxidase-labeled multi-linker as the secondary. Stable SP2/0-pRc/CMV-S or SP2/0-pRc/CMV-MS clones were established through clone screening with G418.

RESULTS: Fragments with anticipated size were harvested after PCR. After recombination and screening, the sequences of the inserted segments in the recombinants were confirmed to be S, preS2S, preS1-preS2S and preS1S encoding genes, determined by sequencing. The results of Western-blot hybridization were positive for the anticipated proteins. Among them, pRc/CMV-S or pRc/CMV-MS demonstrated the highest expressing their respective antigen.

CONCLUSION: Eight recombinant plasmids expressing S, M, L or preS1S proteins are obtained. For hepatitis surface antigen expression in eukaryotic cells, the vector pRc/CMV is superior to pSG5UTPL/Flag, and pRc/CMV-S and pRc/CMV-MS are the most efficient in the pRc/CMV clones. SP2/0 cells stably expressing HBsAg are established, and may be used as target cells for evaluating the CTL activity of a DNA vaccine in vitro.