Factors influencing long-term persistence of anti-HBs after hepatitis B vaccination

In virto priming of the STING signaling pathway enhances the maturation and activation of dendritic cells induced by hepatitis B vaccine

This study investigates the role of the STING signaling pathway in enhancing dendritic cells (DCs) maturation and activation in response to the hepatitis B vaccine. By analyzing the GSE52894 dataset, we compared differentially expressed genes between mature dendritic cells (mDCs) and immature dendritic cells (iDCs). In vitro, iDCs were treated with the STING agonist 2'3'-cGAMP, either alone or in combination with lipopolysaccharide (LPS) or the hepatitis B vaccine, to assess the expression of costimulatory molecules and key signaling molecules in the STING pathway, including STING, pNF-κBp65, and pIRF3. The results indicated that mDCs expressed significantly higher levels of STING mRNA compared to iDCs (P < 0.01). Treatment with 2'3'-cGAMP increased STING expression and activated downstream signaling molecules pNF-κBp65 and pIRF3. Co-treatment with 2'3'-cGAMP and LPS upregulated costimulatory molecules (CD80, CD86, HLA-DR, CD11c) more effectively than LPS alone (P < 0.05). Co-treatment with 2'3'-cGAMP and the hepatitis B vaccine resulted in significantly higher expression of costimulatory molecules compared to vaccine-only treatment. Furthermore, co-treatment with 2'3'-cGAMP and the hepatitis B vaccine enhanced STING, pNF-κBp65, and pIRF3 expression relative to vaccine alone. Mixed lymphocyte reaction assays demonstrated that the 2'3'-cGAMP and hepatitis B vaccine co-treatment group had a significantly stronger effect on the proliferation of CD4+T cells compared to the vaccine-only treatment group. In conclusion, 2'3'-cGAMP enhances DCs maturation and promotes CD4+T cells proliferation in response to the hepatitis B vaccine by activating the STING/IRF3 and STING/NF-κB pathways, highlighting its potential as an adjuvant to improve vaccine efficacy.

Long-Term Immunity and Anamnestic Response Following Hepatitis B Vaccination: A Systematic Review and Meta-Analysis

Using a systematic review and meta-analytic approach, this study determined the durability of HBV immunity and the prevalence of anamnestic response to a booster HBV vaccine dose in individuals previously vaccinated with a 3-dose HBV vaccine series as children or adolescents. Two researchers independently searched PubMed, Embase and Cochrane from inception to 6/1/2023 and performed data extraction. Studies that included individuals with significant comorbidities or < 5 years of follow-up were excluded. Of 2517 potential studies, we analysed 91 eligible studies (193,359 individuals from 208 cohorts [some studies provided data for more than one cohort]). Median age at vaccination was 0 years (range: 0-20.00). After a median follow-up of 10.15 years (range: 5-35), 63.2% (95% CI: 59.3-67.0) retained HBV immunity. HBV immunity declined by 6.62% per follow-up year (Ptrend < 0.0001). In meta-regression adjusting for vaccine type, follow-up time and geographic location, age at vaccination was significantly associated with retaining HBV immunity (adjusted odds ratio [aOR] 1.12 per year, p < 0.0001). Anamnestic response rate (44 studies, 66 cohorts, 29,040 patients) was 90.34% (95% CI: 86.84-92.98), with highest rates in Europe and Asia, but only study setting (clinical versus community-based: aOR 2.21, p = 0.034) was an independent factor. HBV immunity prevalence was about 60% after 10 years following childhood vaccination. Anamnestic response rate was about 90% and varied by study setting. Testing for immunity should be considered in individuals with high exposure risk and distant vaccination history with booster as needed.

Seropositivity of antibody to hepatitis B core antigen among hepatitis B surface antigen-negative vaccinated individuals aged 5-12 years in North West Ethiopia

Background

Infection with the hepatitis B virus (HBV) is still a major global public health concern, especially in Ethiopia. Evidence suggests that some children in Ethiopia who have received hepatitis B vaccinations are still contracting HBV.

Objective

The main aim of this study was to detect antibodies to hepatitis B core antigen (anti-HBc) among vaccinated hepatitis B surface antigen (HBsAg)-negative individuals in North-West Ethiopia.

Methods and materials

A community-based cross-sectional study was conducted among 158 children aged 5-12 years from April 2021 to November 2021. A simple random sampling technique was used to recruit study participants. After 3-5 ml of venous blood was drawn from each study participant, a serum sample was utilized to determine hepatitis B surface antigen (HBsAg) and anti-hepatitis B core antibodies (anti-HBc) by enzyme-linked immunosorbent assay (ELISA). Logistic regression with a 95 % CI was used to show the statistical association.

Results

The total seropositivity of anti-HBc among vaccinated HBsAg-negative participants was 8/158 (5.1 %) (95 % CI: 2.0-9.0). Multivariable logistic regression revealed that children who had a previous history of blood transfusion were six times (AOR: 6.135, 95 % CI: 4.063, 10.752) (P < 0.006) more likely to develop anti-HBc. Moreover, children who had a previous history of surgery were five times (AOR: 5.116, 95 % CI: 3.123, 8.718) (P < 0.002) more likely to become anti-HBc seropositive.

Conclusion

There was a significant seroprevalence of anti-HBc in our study area, suggesting possible exposure to the virus despite immunization.

The Impact of Smoking on Long-Term Protection Following Hepatitis B Vaccination: A 24-Year Cohort Study

The hepatitis B vaccination-induced immune response has been demonstrated to be associated with a number of factors, including age, sex, BMI, and the presence of comorbidities. Additionally, modifiable determinants such as smoking have been identified as influencing the response to vaccination. However, despite the evidence that smokers are at an increased risk of not responding to vaccination, the long-term effects of smoking on antibody persistence remain poorly understood. This study aims to assess the impact of smoking habits on long-term immunity following the primary vaccination cycle. Participants were required to have received a standard three-dose vaccine schedule in childhood, without subsequent doses, and to be between 18 and 24 years of age. Data on age, sex, BMI, age of administration of the first vaccine dose, and time between doses were collected. An antibody concentration < 10 IU/L was considered as non-protective. A total of 2133 individuals were included, 14.2% of whom were smokers. The mean age was 20.28 ± 0.92 years. The probability of having a non-protective antibody concentration was significantly higher in smokers than in non-smokers (AOR: 1.287; 95% CI: 1.002-1.652). The detrimental effects of smoking extend beyond the immediate effects on the vaccine response, also impairing the long-term immune response in individuals who received vaccinations during childhood.

Safety and immunogenicity of the co-administered Na-APR-1 and Na-GST-1 hookworm vaccines in school-aged children in Gabon: a randomised, controlled, observer-blind, phase 1, dose-escalation trial

BACKGROUND

A human hookworm vaccine is being developed to protect children against iron deficiency and anaemia associated with chronic infection with hookworms. Necator americanus aspartic protease-1 (Na-APR-1) and N americanus glutathione S-transferase-1 (Na-GST-1) are components of the blood digestion pathway critical to hookworm survival in the host. Recombinant Na-GST-1 and catalytically inactive Na-APR-1 (Na-APR-1[M74]) adsorbed to Alhydrogel were safe and immunogenic when delivered separately or co-administered to adults in phase 1 trials in non-endemic and endemic areas. We aimed to investigate the safety and immunogenicity of these antigens in healthy children in a hookworm-endemic area.

METHODS

This was a randomised, controlled, observer-blind, phase 1, dose-escalation trial, conducted in a clinical research centre, in 60 children aged six to ten years in Lambaréné, a hookworm-endemic region of Gabon. Healthy children (determined by clinical examination and safety laboratory testing) were randomised 4:1 to receive co-administered Na-GST-1 on Alhydrogel plus Na-APR-1(M74) on Alhydrogel and glucopyranosyl lipid A in aqueous formulation (GLA-AF), or co-administered ENGERIX-B hepatitis B vaccine (HBV) and saline placebo, injected into the deltoid of each arm. Allocation to vaccine groups was observer-masked. In each vaccine group, children were randomised 1:1 to receive intramuscular injections into each deltoid on two vaccine schedules, one at months 0, 2, and 4 or at months 0, 2, and 6. 10 μg, 30 μg, and 100 μg of each antigen were administered in the first, second, and third cohorts, respectively. The intention-to-treat population was used for safety analyses; while for immunogenicity analyses, the per-protocol population was used (children who received all scheduled vaccinations). The primary outcome was to evaluate the vaccines' safety and reactogenicity in healthy children aged between six and ten years. The secondary outcome was to measure antigen-specific serum IgG antibody levels at pre-vaccination and post-vaccination timepoints by qualified ELISAs. The trial is registered with ClinicalTrials.gov, NCT02839161, and is completed.

FINDINGS

Between Jan 23 and Oct 3, 2017, 137 children were screened, of whom 76 were eligible for this trial. 60 children were recruited, and allocated to either 10 μg of the co-administered antigens (n=8 for each injection schedule), 30 μg (n=8 for each schedule), 100 μg (n=8 for each schedule), or HBV and placebo (n=6 for each schedule) in three sequential cohorts. Co-administration of the vaccines was well tolerated; the most frequent solicited adverse events were mild-to-moderate injection-site pain, observed in up to 12 (75%) of 16 participants per vaccine group, and mild headache (12 [25%] of 48) and fever (11 [23%] of 48). No vaccine-related serious adverse events were observed. Significant anti-Na-APR-1(M74) and anti-Na-GST-1 IgG levels were induced in a dose-dependent manner, with peaks seen 14 days after the third vaccinations, regardless of dose (for Na-APR-1[M74], geometric mean levels [GML]=2295·97 arbitrary units [AU] and 726·89 AU, while for Na-GST-1, GMLs=331·2 AU and 21·4 AU for the month 0, 2, and 6 and month 0, 2, and 4 schedules, respectively). The month 0, 2, and 6 schedule induced significantly higher IgG responses to both antigens (p=0·01 and p=0·04 for Na-APR-1[M74] and Na-GST-1, respectively).

INTERPRETATION

Co-administration of recombinant Na-APR-1(M74) and Na-GST-1 to school-aged Gabonese children was well tolerated and induced significant IgG responses. These results justify further evaluation of this antigen combination in proof-of-concept controlled-infection and efficacy studies in hookworm-endemic areas.

FUNDING

European Union Seventh Framework Programme.

Antibody persistence of standard versus double three-dose hepatitis B vaccine in liver transplant children: a randomized controlled trial

Rapid hepatitis B (HB) surface antibody (anti-HBs) loss is prevalent after liver transplantation (LT). Herein, we evaluated anti-HBs persistence after HB vaccination using two regimens in LT children. We recruited 66 previously immunized LT children with anti-HBs level of < 100 mIU/mL. Participants were randomly reimmunized with standard-three-dose (SD) and double-three-dose (DD) intramuscular HB vaccination at 0, 1, and 6 months. Anti-HBs were assessed at every outpatient visit. Antibody loss defined as anti-HBs levels < 100 mIU/mL after three-dose vaccination. After three-dose vaccination, 81.8% and 78.7% of participants in the SD and DD groups, had anti-HBs levels > 100 mIU/mL, with a geometric mean titer (GMT) of 601.68 and 668.01 mIU/mL (P = 0.983). After a mean follow-up of 2.31 years, the anti-HBs GMT was 209.81 and 212.61 mIU/mL in the SD and DD groups (P = 0.969). The number of immunosuppressants used and an anti-HBs level < 1 mIU/mL at baseline were independently associated with anti-HB loss. The DD regimen strongly increased the risk of anti-HBs loss (adjusted hazard ratio, 2.97 [1.21-7.31]; P = 0.018). The SD HB reimmunization regimen effectively maintained protective anti-HBs levels in children undergoing LT, making it the preferred regimen for such children with anti-HB loss.Trial registration: TCTR20180723002.

Epidemiology of Chronic Hepatitis B Infection in the Cohort of College Students with Vaccination in Taiwan

After the mass vaccination project in Taiwan, the prevalence of the hepatitis B virus (HBV) infection for the college-aged population of 18 to 21 years is uncertain. We aimed to investigate the prevalence of hepatitis B markers in different birth cohorts. A total of 38,075 students in universities in Kaohsiung area undergoing entrance examinations between July 2006 to September 2020 were included. Seroprevalence of the hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody (anti-HBs) status and laboratory data were collected. The seropositive rate of HBsAg was less than 1% for students born after 1991. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST), were significantly higher, and body mass index (BMI) was significantly lower in HBV carriers compared to those who were not carriers (all p < 0.001). Multivariate logistic regression showed that age, male, higher BMI, and positive HBsAg were risk factors of abnormal ALT value. A decrease in the positive rate of anti-HBs which was significantly higher in the cohort of plasma-derived vaccines than recombinant vaccines was found. We concluded that there were decreasing trends in seropositive rates of HBsAg and anti-HBs for students of the college-aged population in the Kaohsiung area. The status of HBsAg was a predictive factor of abnormal ALT levels. The period effect on anti-HBs seropositivity for DNA recombinant vaccine somehow existed.