Boosting of Hepatitis B Virus-Specific T Cell Responses After Pegylated-Interferon-α-2a Therapy for Hepatitis B e Antigen-Positive Pediatric Patients.

Treatment of chronic hepatitis B with pegylated-interferon-α-2a (PegIFNα) in pediatric patients can lead to a higher rate of hepatitis B virus (HBV) surface antigen (HBsAg) loss than in adults. However, the mechanism of underlying immune response is not clear. The aim of this study was to explore innate and adaptive immunity, especially HBV-specific T cell responses in hepatitis B e antigen (HBeAg)-positive pediatric patients, who have experienced HBsAg loss. Isolated lymphocytes of 20 HBeAg-positive pediatric patients were collected every 12 weeks until treatment was stopped. The phenotype of T/natural killer (NK) cells and function of HBV-specific T cells were analyzed by flow cytometry. The frequency of CD69 and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) expressed on T cells and TRAIL on CD56hi NK cells in patients with HBsAg loss was remarkably higher compared with nonresponse patients. Furthermore, in vitro peptide stimulation of HBV-specific T cell responses was increased in patients with HBsAg loss when compared with week 0 and 48, and correlated with decline of viral load. The PegIFNα therapy in pediatric patients triggered T/NK cell activation and HBV-specific T cell responses, thereby contributing to successful viral control.

Association of characteristics of HBV quasispecies with hepatitis B surface antigen seroconversion after pegylated interferon-α-2a treatment in child patients.

BACKGROUND: The correlation between hepatitis B surface antigen (HBsAg) seroconversion and the characteristics of HBV quasispecies (QS) before and during pegylated interferon-α-2a (PEG-IFN-α-2a) treatment in hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) children has not yet been reported. METHODS: 35 patients, including 18 HBsAg seroconverters (SS) and 17 non-seroconverters (SN), were enrolled. Serum samples were collected before treatment and at weeks 12 and 24 of treatment. Sequences within the basal core promoter/pre-core (BCP/PC) and S/reverse transcriptase (S/RT) region were analysed by next-generation sequencing. RESULTS: There was no significant difference in the baseline diversity of HBV QS (Shannon entropy [Sn]; Hamming distance [HD]) in either region between the two groups. The baseline mutations A1762T/G1764A, C1913A, and T2003A/G or C2004T were correlated with non-response to therapy (P=0.025, P=0.036, P=0.032, respectively). After 24 weeks of therapy, HBV diversity within the BCP/PC region in the SS group notably declined (Sn: P=0.002; HD: P=0.011), while that of the SN group was nearly unchanged. As for the S/RT region, 24 weeks of treatment made no significant difference on QS diversity in either group. CONCLUSIONS: Our data demonstrated that the baseline viral mutations and dynamic changes in HBV QS diversity within the BCP/PC region were closely related to HBsAg seroconversion in HBeAg-positive CHB children treated with PEG-IFN-α-2a.

Quasispecies characteristics in mother-to-child transmission of hepatitis B virus by next-generation sequencing.

OBJECTIVES: To identify within-host quasispecies characteristics of hepatitis B virus (HBV) in mothers and children infected via mother-to-child transmission (MTCT). METHODS: Using next-generation sequencing (NGS), we analyzed sequences within the non-overlapping pre-core/core (pre-C/C) gene in 37 mother-child pairs. RESULTS: Phylogenetic and Highlighter analyses suggested that both a single strain and multiple distinct strains may be transmitted in MTCT of HBV. However, analysis of reassembled viral sequences revealed a relatively narrow distribution of variants in children, which was confirmed by a lower viral diversity in children than that in mothers. New closely related variants with combinations of two to five high-frequency mutations were observed in seven children with elevated ALT levels; the new variants out-competed the transmitted maternal variants to become the dominant strains in five of them. Furthermore, 30 mutations with a frequency >1% of all viruses within-host were present in those children; the mutations caused 19 amino-acid substitutions. Interestingly, almost all were located within the well-known T-cell or B-cell epitopes. CONCLUSIONS: There are restrictive changes that occur in the early stages of chronic HBV infection through MTCT with different clinical consequences. These data might have important implications for future investigations of interrelated immunopathogenesis and therapeutic strategies.

[Efficacy of interferon-alpha therapy for HBeAg-negative chronic hepatitis B and its influencing factors].

OBJECTIVE: To investigate the efficacy of interferon-alpha (IFN-alpha) therapy for HBeAg-negative chronic hepatitis B. METHODS: Sixty-five Chinese HBeAg-negative chronic hepatitis B patients were treated with 5 MU recombinant rIFN-alpha 1b subcutaneously thrice weekly for 5 to 24 months, followed by 12 months of treatment-free follow-up; one hundred and eighty-eight Chinese HBeAg-positive patients served as controls. For each patient, serum alanine transaminase (ALT) was measured biochemically and serum HBV DNA level was detected with fluorescent-quantitative PCR, HBeAg with enzymoimmunoassay every 1 to 3 months during therapy and during the follow-up period. HBeAg loss (only for HBeAg-positive cases), HBV DNA undetectable, and ALT normalization: the three together were considered a combined response. RESULTS: Rates of combined response were similar in HBeAg-negative patients (58.5%, 38/65) or HBeAg-positive ones at the end of treatment (weighted chi square test, chi2 = 1.878, P<0.05), but were higher at the end of the follow-up period in the HBeAg-negative cases (75.4%, 49/65) (weighted chi square test, chi2 = 4.796, P<0.05). Furthermore, relapse rates at the end of the follow-up period, were also similar in HBeAg-negative patients (15.8%, 6/38) or HBeAg positive (chi2 = 0.205, P>0.05). Combined response was achieved at a median of 6.0 months (2-16 months) of treatment course in HBeAg-negative patients while at a median of 6.0 months (1-22 months) in HBeAg-positive cases (Z = -0.186, P>0.05, by the Wilcoxon rank sum test). The only factor predictive of combined response, by binary logistic regression analysis, was inflammatory activity in the liver biopsy. Gender, age, baseline ALT level, baseline HBV DNA level, and anti-HBe were not predictive factors. CONCLUSION: Interferon-alpha therapy induces a similar primary and sustained response in HBeAg-negative and in HBeAg-positive chronic hepatitis B patients.