Determining Whether Prophylactic Antiviral Treatment Is Necessary in HBsAg-Negative/HBcAb-Positive Patients Receiving Allogeneic Hematopoietic Stem Cell Transplantation

Epstein-Barr virus reactivation correlates with worse outcomes for patients exposed to hepatitis B virus after haploidentical hematopoietic stem cell transplantation

Hepatitis B virus (HBV)has a high, chronic infection rate in Asian populations, but only few studies have analyzed the effect of Epstein-Barr virus (EBV) or Cytomegalovirus (CMV) reactivation in patients exposed to HBV after haploidentical hematopoietic stem cell transplantation (haplo-HSCT). This study aimed to assess the clinical outcomes of these patients. We conducted a retrospective research including 61 patients exposed to HBV after undergoing haplo-HSCT. The patients were classified into two groups: the CMV reactivation group and no CMV reactivation group. The results were compared between the two groups using the K-W test for continuous variables, Pearson's chi-square test for categorical variables, Kaplan-Meier curves to estimate overall survival (OS) and leukemia-free survival (LFS), and a Cox proportional hazards model to analyze multivariable influences. The 3-year cumulative HBV reactivation rate was 8.2%. The median duration of HBV reactivation was 16 months (16-22 months) after haplo-HSCT. The CMV reactivation group had a higher cumulative incidence of HBV reactivation than the group without CMV reactivation. The EBV reactivation was substantially higher in the CMV reactivation group compared to that in the no CMV reactivation group (37.0% vs.5.9% respectively; P = 0.002). Furthermore, EBV reactivation was a risk factor for 1-year LFS and 1-year OS. Based on our data, EBV reactivation was related to worse outcomes in patients exposed to HBV after haplo-HSCT, whereas CMV reactivation was not.

An update about beneficial effects of medicinal plants in aquaculture: A review

Aquaculture is an essential and growing component of agricultural and global ecosystems worldwide. Aquaculture provides more than 25% of the total aquatic food consumption by humans. The development of the aquaculture industry should be followed in successive industrial years, and therefore it is necessary to pay attention to the management and type of farming system that is compatible with the environment. The use of antibiotics for disease control has been criticised for their negative effects, including the emergence of antibiotic-resistant bacteria, the suppression of the immune system and the environment, and the accumulation of residue in aquatic tissues. The use of these products reduces the need for treatments, enhances the effect of vaccines, and, in turn, improves production indicators. Medicinal plants have increasingly been used in recent years as a disease control strategy in aquaculture, boosting the immune system of aquatic animals and helping to develop strong resistance to a wide range of pathogens. Therefore, this review aims to provide an overview of the recent evidence on the beneficial use of medicinal plants to promote growth and strengthen the immune system in farmed aquatic animals.

Adoptive immune transfer from donors offers Anti-HBV protection to HBsAb-negative patients after Allo-HSCT

Adoptive transfer of hepatitis B virus (HBV) immunity may occur following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Here, we investigated the adoptive transfer of HBV immunity in 112 patients without HBV surface antibody (HBsAb) (HBsAb-) at the time of their first allo-HSCT. After allo-HSCT, HBV-DNA（87.5%） and HBsAg（11.1%%）cleared in HBsAg+ patients. All HBsAg- patients acquired HBsAb immediately. Nevertheless, HBsAb titers subsequently declined, and 39/67 (58.2%) patients lost HBsAb during follow-up. The 5-year overall survival (OS) was better in patients who lost HBsAb. Multivariate analysis showed that the independent risk factors for OS were lack of cytomegalovirus (CMV) clearance, acute graft-versus-host disease (aGVHD), and no HBsAb loss. Overall, adoptive immune transfer offers anti-HBV protection to patients without HBsAb, as they acquire HBsAb and clear HBV-DNA and HBsAg, while HBsAb loss after allo-HSCT predicts better survival.

Hepatitis B virus vaccination after allogeneic hematopoietic cell transplantation prevents post-transplant HBV reactivation

BACKGROUND

Hepatitis B virus (HBV) reactivation in allogeneic hematopoietic-cell transplant (HCT) recipients with evidence of pre-transplantation resolved HBV infection is an important cause of morbidity, usually occurring a year or later after HCT.

OBJECTIVES

We retrospectively studied a cohort of allogeneic HCT recipients with resolved HBV infection, some of whom were vaccinated for HBV following transplantation, to understand if post-HCT HBV vaccination influenced the risk of HBV reactivation.

STUDY DESIGN

The study included all patients with resolved HBV who underwent allogeneic HCT at our institution between 1/1/2000 and 12/31/2015, where HBV vaccination starting at 1 year after HCT became standard in 2012 and antiviral prophylaxis is not utilized. Resolved HBV infection was defined as positive HBV-core IgG (HBcAb), negative HBV-surface antigen (HBsAg) and undetectable HBV DNA before HCT. HBV reactivation was defined as development of detectable HBsAg and HBV DNA after HCT. Follow up for outcomes concluded 1/1/2018.

RESULTS

Among 136 patients with resolved HBV before HCT, 19 developed reactivation during follow up (cumulative incidence 14%). Median time to HBV reactivation was 21 months (range, 2-47 months). The cumulative probability of HBV reactivation among HCT recipients who survived for a year or more after transplant without early HBV reactivation and were HBV-vaccinated versus those who were unvaccinated was 2.9% vs. 10.0 % at two years and 6.6% vs. 26.5% at 4 years post-HCT (P = 0.03, Gray's test). In a time-dependent Cox model, the adjusted hazard ratio (aHR) of HBV reactivation in patients with pre-transplant HBsAb levels greater than 10 IU/L was 0.34 (95% confidence interval [CI], 0.13-0.90). The aHR of HBV reactivation in patients who were vaccinated with 2 or more doses of recombinant HBV vaccine after HCT was 0.18 (95% CI, 0.04-0.80) compared to those who received 1 or no post-HCT vaccine doses.

CONCLUSIONS

HBV reactivation is a late complication of allogeneic HCT in at-risk recipients, particularly in those with low pre-HCT HBsAb. HBV vaccination starting 1 year after HCT may be protective.

Hepatitis B Virus Infection in Patients Receiving Allogeneic Hematopoietic Stem Cell Transplantation

Considering a steady increase in the number of allogeneic hematopoietic stem cell transplantations (allo-HSCT) worldwide and the significant proportion of the world’s population that has been exposed to hepatitis B virus (HBV) infection, HBV reactivation following allo-HSCT remains an important issue for post-transplant morbidity and mortality. Antiviral prophylaxis can reduce HBV replication, severity of HBV-related hepatitis, and mortality; therefore, identification of patients at risk is crucial. It is recommended that all recipients and donors should be screened for active or prior HBV infection, including HBsAg, antiHBc, and antiHBs. Adoptive immunity transfer from the donor seems to have protective effects against HBV reactivation. Antiviral prophylaxis should be initiated in all HBsAg-positive patients. HBsAg-negative, antiHBc-positive patients remain at risk; therefore, antiviral prophylaxis should be considered if baseline serum HBV DNA is detectable. In HBsAg-negative, antiHBc-positive patients without detectable HBV DNA, close monitoring of viral load with an on-demand therapy is necessary. Entecavir or tenofovir rather than lamivudine are more appropriate for the emergence of lamivudine resistance. The treatment duration remains unclear, with 6- to 12-month therapy after cessation of immunosuppressive therapy commonly recommended. Here we review the updated evidence and recent recommendations regarding HBV reactivation in patients undergoing allo-HSCT for individualized therapy.

Hepatitis B Seropositive Status in Recipients or Donors Is Not Related to Worse Outcomes after Haploidentical Hematopoietic Stem Cell Transplantation

Hepatitis B virus (HBV) has a high rate of chronic infection in Asian populations, and only limited studies have been performed to analyze the impact of HBV-seropositive haploidentical hematopoietic stem cell transplantation (haplo-HSCT) recipients and donors. The present study aimed to evaluate the effect on clinical outcomes in those patients. We conducted a retrospective study enrolling 237 consecutive patients undergoing first haplo-HSCT. The patients were classified into 3 groups: recipient HBV-positive group (R+D-; n = 62), donor HBV-positive group (D+; n = 83), and HBV-negative group (R-D-; n = 92). Corresponding prophylactic antiviral treatment was given in the R+D- and D+ groups. The results were compared among the 3 groups using the Kruskal-Wallis test for continuous variables, Pearson's chi-square test for categorical variables, the competing-risk method to evaluate cumulative incidence, Kaplan-Meier curves to estimate overall survival (OS) and disease-free survival (DFS), and a Cox proportional hazard model to analyze multivariable influences. The 3-year cumulative HBV reactivation rate was 4.2%. The median time to HBV reactivation was 845 days (range, 545 to 1439 days) after haplo-HSCT. The R+D- group tended to have a higher cumulative incidence of HBV reactivation compared with the D+ group (11.8% versus 3.1%; P = .080). Significant differences in the causes of hepatic damage were observed among the 3 groups (P = .017), and all patients with acute hepatitis B after haplo-HSCT were from the R+D- group. Multivariate analysis showed that pretransplantation HBV status was associated with cytomegalovirus reactivation (R+D- versus R-D-: hazard ratio, 1.514; 95% confidence interval, 1.060 to 2.163; P = .023). The 3-year OS and DFS, 3-year cumulative incidence of nonrelapse mortality (NRM), rates of relapse and graft-versus-host disease (GVHD), and causes of death were comparable among the 3 groups. Pretransplantation HBV serostatus had no significant effect on OS, DFS, NRM, relapse, or GVHD in the multivariate analysis. Based on our data, seropositivity for hepatitis B surface antigen (HbsAg) or core antibody (HBcAb) in donors or recipients before transplantation did not negatively affect the overall outcome after haplo-HSCT under the premise of proper antiviral prophylaxis along with regular post-transplantation surveillance, and HBV seropositivity should not be considered a contraindication to haplo-HSCT.

Management of Hepatitis B Virus in Allogeneic Hematopoietic Stem Cell Transplantation

The high morbidity of HBV reactivation following allogeneic hematopoietic stem cell transplantation (allo-HSCT) is partially due to the intense immunologic potency of complex therapeutic regimens, the use of antithymocyte globulin and calcineurin inhibitors to prevent graft versus-host disease (GVHD), prolonged immune reconstitution, and hematological malignancies infected with hepatitis B virus (HBV). Immunosuppression results in the reactivation of HBV replication from covalently closed circular DNA (cccDNA) residing in hepatocytes. However, the role of viral mutations during HBV reactivation needs to be validated. All individuals scheduled to receive allo-HSCT or wish to donate stem cells should be screened for hepatitis B surface antigen (HBsAg), antibodies to hepatitis B core (anti-HBc), and HBV-DNA. HBsAg-positive recipients of allo-HSCT have a high risk of HBV reactivation; thus, they should receive prophylactic antiviral therapy. The high barrier to resistance nucleos(t)-ide analogs (NAs) seems to be superior to the low barrier agents. Resolved-HBV recipients have a lower risk of HBV reactivation than HBsAg-positive recipients. Although prophylactic antiviral therapy remains controversial, regular monitoring of alanine transaminase (ALT) and HBV-DNA combined with preemptive antiviral treatment may be an optimized strategy. However, optimal antiviral therapy duration and time intervals for monitoring remain to be established. Accepting stem cells from HBsAg-positive donors is associated with a risk of developing HBV-related hepatitis. The overall intervention strategy, including donors and recipients, may decrease the risk of HBV-related hepatitis following HSCT from HBsAg positive stem cells. In this review, we summarize the issues of HBV in allo-HSCT, including HBV reactivation mechanism, HBsAg-positive recipients, HBV-resolved infection recipients, and donor-related factors, and discuss their significance.