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Viral Immunity in Solid Organ Transplant Recipients: Monitoring Of The Response To Hepatitis B Booster Vaccination

Not yet recruiting
Conditions
HBV
Liver Transplantation
Kidney Transplantation
Interventions
Registration Number
NCT06307808
Lead Sponsor
University Hospital, Grenoble
Brief Summary

Solid Organ Transplantation (SOT) is made possible by the use of a lifelong immunosuppressive treatment. This treatment limits the response of the immune system, enabling long-term survival of the transplanted organ, but also leading to weaker anti-infectious responses.

In this study, we will compare the response to a booster Hepatitis B vaccination (HBV) in SOT patients, either after kidney or liver transplantation. We will also compare the immune response depending on the immunosuppressive treatment.

In order to provide a detailed picture of the immune response, we will investigate the usual serological response (anti-HBs antibodies), but also the cellular memory (both T and B) using ELISpot assays and flow-cytometry, over a 6 months period following booster vaccination.

Detailed Description

Solid Organ Transplantation (SOT) is the reference treatment for end stage kidney disease (Kidney Transplantation, KT) and liver failure (Liver Transplantation, LT). As of 2023, an immunosuppressive treatment remains mandatory for long-term graft survival. This treatment translates into a weaker response to vaccines. The recent example of Severe Acute Respiratory Syndrom (SARS) - Coronavirus (CoV), SARS-CoV-2, showed different vaccinal responses depending on the immunosuppressive drug, comparing belatacept- to tacrolimus-based immunosuppression.

Hepatitis B virus (HBV)-vaccination is recommended in chronic kidney failure and liver failure. However, post-transplantation, a loss of HBV seroprotection is seen in \~ 30 % of the patients. A booster HBV vaccine dose is recommended in such case, but the evaluation of the response to this booster dose is limited.

In the Viral Immunity in TrAnsplanted patients depending on iMmunosupressIoN (VITAMIN) study, investigators will investigate the effect of a HBV-vaccine booster on the immune system, comparing KT recipients treated with Belatacept with KT and LT recipients treated with Tacrolimus. The VITAMIN study is a prospective observational study recruiting KT and LT recipients from the time of a booster HBV vaccine injection and over the following 6 months. The idea is to take advantage of this very particular sensitizing event, at a defined timepoint, to investigate the immune response to HBV through vaccination. Investigators will focus on comparing the immunological state before and after vaccination, in kidney and liver transplant recipients receiving immunosuppression.

The immunological state will be described through 1/ the antibody response, 2/ its phenotype (both exploring the T cell compartment and the B cell compartment, including memory B cells, using flow cytometry) and 3/ its functional response (through the ELISpot assessment of the T response against HBV HBs antigen). Sequential blood samples will be taken, using Peripheral Blood Monocytic Cells (PBMC). Also, investigators will focus on HBV-specific memory B cells, to detect potential antibody secreting cells. This project will provide a longitudinal picture of all immune compartments stimulated by HBV vaccination. This longitudinal picture will be compared between tacrolimus-treated KT and LT recipients and belatacept-treated KT recipients.

The main objective is to compare the serological response (anti-HBs antibodies) between tacrolimus- and belatacept-treated patients. The secondary objective is to describe and compare the phenotype and functional T and B responses between tacrolimus- and belatacept-treated patients.

Comparing different immunosuppressive regimen through the immunological responses, investigators aim at improving the personalization of the immunosuppressive treatment.

Recruitment & Eligibility

Status
NOT_YET_RECRUITING
Sex
All
Target Recruitment
66
Inclusion Criteria
  • Kidney or liver transplant recipients
  • Grenoble University Hospital regular follow-up
  • Tacrolimus or belatacept treated
  • Clinical indication for HBV booster vaccination
Exclusion Criteria
  • Pregnancy or lactating woman
  • History of HBV infection (either anti-Hepatitis B capside antigen (HBc), positivity or HBV-DNA positivity)

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Kidney transplant recipients, tacrolimus treatedTacrolimusPrevalent kidney transplant recipients, receiving tacrolimus as main immunosuppresant
Liver transplant recipients, tacrolimus treatedTacrolimusPrevalent liver transplant recipients, receiving tacrolimus as main immunosuppressant
Kidney transplant recipients, belatacept treatedBelataceptPrevalent kidney transplant recipients, receiving belatacept as main immunosuppressant
Primary Outcome Measures
NameTimeMethod
Titer of anti-HBs ELISA antibodyFrom enrollment to 6 months after inclusion

Anti-HBs HBV serological response

Secondary Outcome Measures
NameTimeMethod
Number of anti-HBs memory B cellsFrom enrollment to 6 months post-enrollment

B-ELISpot anti-HBs memory B cells

Trial Locations

Locations (1)

Grenoble University Hospital

🇫🇷

Grenoble, Aura, France

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