Hepatitis B Virus and Hepatitis D Virus Recurrence in Patients Undergoing Liver Transplantation for Hepatitis B Virus and Hepatitis B Virus Plus Hepatitis D Virus

BACKGROUND

In this study, we retrospectively analyzed the recurrence of hepatitis B virus (HBV) and hepatitis D virus (HDV) infection after liver transplantation for HBV and HBV+HDV co-infection.

METHODS

Data from patients infected with HBV and HBV+HDV who underwent liver transplantation between March 2003 and June 2013 at the Liver Transplantation Institute of Inonu University were analyzed retrospectively. A total of 255 patients were included in the study. Group 1 (n = 127) comprised patients who underwent liver transplantation because of HBV, and group 2 (n = 128) comprised patients who underwent liver transplantation because of HBV+HDV. A positive HDV antibody serologic test result was taken to indicate liver disease caused by HBV+HDV.

RESULTS

Thirteen of 255 were positive for the HBs Ag (5.1%). Nine (7.1%) and 4 (3.1%) patients were positive for the HBs Ag in groups 1 and 2, respectively (7.1%); the difference was not significant (P = .150). No HDV recurrence was detected in either group. The average time to HBs Ag seroconversion in 13 patients was 7.8 months after surgery (6.34 months in group 1 and 11.1 months in group 2).

CONCLUSIONS

In our study, recurrence rate of HBV after liver transplantation is not statistically different than the recurrence rate of HBV+HDV co-infection. A low recurrence rate was achieved by the prophylaxis protocol in use at our center. There is no standard protocol for prevention of HBV and HDV recurrence; therefore, we need new studies.

The long-term efficacy of combining nucleos(t)ide analog and low-dose hepatitis B immunoglobulin on post-transplant hepatitis B virus recurrence

BACKGROUND

The aim of this study was to determine the long-term efficacy of nucleos(t)ide analog (NA) and low-dose hepatitis B immunoglobulin (HBIG) combination treatment for preventing post-transplant hepatitis B virus (HBV) recurrence.

METHODS

A total of 296 patients with HBV-associated liver disease who underwent liver transplantation (LT) were enrolled. A combination of a daily NA and low-dose HBIG was used after LT.

RESULTS

The median follow-up period was 46 months. HBV recurrence occurred in eight patients. The cumulative probability of HBV recurrence at 1, 3, 5, and 7 years was 1%, 3%, 3%, and 4%, respectively. Seven were on lamivudine (LMV) or adefovir dipivoxil (ADV), or LMV and ADV and HBIG combination treatment and one entecavir (ETV) and HBIG. With Cox regression analysis, HBV recurrence was determined to be associated with the presence of hepatocellular cancer (HCC) prior to LT (HR: 12.3, P=.02). Overall, 44 patients died. Survival was significantly better in the ETV or tenofovir disoproxil fumarate (TDF) and HBIG group than the other group (P<.001).

CONCLUSION

The combination of ETV or TDF and low-dose HBIG achieved a more favorable prophylaxis against HBV recurrence after LT. The presence of HCC prior to LT was associated with post-transplant HBV recurrence.

Low-dose short-term hepatitis B immunoglobulin with high genetic barrier antivirals: the ideal post-transplant hepatitis B virus prophylaxis?

BACKGROUND

Low-dose hepatitis B immunoglobulin (HBIG) and nucleos(t)ides analogs (lamivudine/adefovir) used for the prevention of hepatitis B virus (HBV) recurrence after liver transplantation (LT) are associated with some risk of HBV recurrence and antiviral resistance.

METHODS

The study cohort included 176 patients (at least >12 months follow-up) with HBV cirrhosis/hepatocellular carcinoma who received secondary prophylaxis with indefinite entecavir/tenofovir after living-donor LT (LDLT). All patients received 10,000 IU intravenous HBIG in anhepatic phase followed by 600-1000 IU intramuscularly daily for 7 days, weekly for 3 weeks, and then monthly, to keep antiHBs levels >100 mIU/mL for 1 year. Hepatitis B surface antigen (HBsAg) and HBV DNA were tested every 6 months.

RESULTS

The study cohort is composed of 157 men and 19 women, mean age 47.9 ± 10.1 years, all HBsAg positive, 35 (19.8%) had HBV DNA >2000 IU/mL before LT. After LT, patients received entecavir (n = 126, 71.5%), tenofovir (n = 20, 11.3%), or a combination of entecavir and tenofovir (n = 30, 17% for 3 months), followed by entecavir alone. During follow-up of 43 (12-117) months, 2 patients (including 1 with non-compliance) had HBV recurrence.

CONCLUSION

In a large cohort of LDLT recipients for HBV-related liver disease, use of low-dose short-term HBIG with high genetic barrier drugs results in a substantially lower incidence of HBV recurrence, even in high-risk patients.

High affinity mouse-human chimeric Fab against hepatitis B surface antigen

AIM

Passive immunotherapy using antibody against hepatitis B surface antigen (HBsAg) has been advocated in certain cases of Hepatitis B infection. We had earlier reported on the cloning and expression of a high affinity scFv derived from a mouse monoclonal (5S) against HBsAg. However this mouse antibody cannot be used for therapeutic purposes as it may elicit anti-mouse immune responses. Chimerization by replacing mouse constant domains with human ones can reduce the immunogenicity of this antibody.

METHODS

We cloned the V(H) and V(L) genes of this mouse antibody, and fused them with CH1 domain of human IgG1 and C(L) domain of human kappa chain respectively. These chimeric genes were cloned into a phagemid vector. After initial screening using the phage display system, the chimeric Fab was expressed in soluble form in E. coli.

RESULTS

The chimeric Fab was purified from the bacterial periplasmic extract. We characterized the chimeric Fab using several in vitro techniques and it was observed that the chimeric molecule retained the high affinity and specificity of the original mouse monoclonal. This chimeric antibody fragment was further expressed in different strains of E. coli to increase the yield.

CONCLUSION

We have generated a mouse-human chimeric Fab against HBsAg without any significant loss in binding and epitope specificity. This chimeric Fab fragment can be further modified to generate a full-length chimeric antibody for therapeutic uses.