Study for Detection of Donor-derived Cell-free DNA After Renal Transplantation Using Devysers NGS-based Chimerism Assay.

• Conditions: Cell-Free Nucleic Acids

• Registration Number: NCT05226936
• Lead Sponsor: Sheba Medical Center

Brief Summary

The aim of this study is to evaluate highly sensitive quantitative tests for early molecular detection of graft rejection and associated immune response from liquid biopsies in the blood from patients undergoing renal transplantation and secondly, to evaluate the evolution of de-novo HLA antibodies following renal transplantation. Furthermore, we are interested in the correlation of tissue damage caused by rejection, as measured by the presence of dd-cfDNA, and the presence of de-novo HLA antibodies.

Detailed Description

Each year 40-60 patients undergo renal transplant with a living donor (LD) at Karolinska University Hospital. Prior to transplantation, these patients and their donors are investigated for their immunological compatibility. This includes cytotoxic- and flow cytometric crossmatches, HLA typing as well as determination of possible presence of panel-reactive HLA antibodies (PRA). Normally these investigations are performed 2-3 months prior to renal transplantation. Once a patient has been accepted for transplantation with a given living donor, they will, prior to transplantation be asked whether they are interested in taking part of the present study. If the patient and the donor do accept, we will collect 15 mL of blood prior to transplantation using suitable sample collection tubes (Cell-Free BCT tubes). This sample will be used for screening patient and donor for specific genetic markers. Furthermore, the pretransplant samples will be used for determining the presence or absence of HLA antibodies for each patient. We aim to include up to 50 patients in the current study.

During the first 24-48 hrs after transplantation, two more samples (10 mL) from the patient will be collected to measure the potential presence of dd-cfDNA including cell-free particles such as exosomes. The cell-free DNA and RNA from all samples will be extracted, stored frozen and later sequenced. Following transplantation and initiation of the immunosuppressive therapy, samples for analysis will be obtained once every week for up to 3 months. All collected samples will be either analysed immediately or frozen for future analysis. Stored frozen samples could, at a later time point, be thawed, batched and analysed using molecular techniques including sequencing for measuring dd-cfDNA or analysis of the presence of HLA-antibodies using commercial bead-technologies (Luminex or Immucor). Results from these assays will be added to a dedicated database. The obtained laboratory results will be compared to clinical outcome including graft survival, patient survival, clinical and subclinical rejections etc. as well as other laboratory data (e.g. results from pathological examination of the graft, clinical chemistry, concentration of immunosuppressive drugs etc).

Study Timeline

• Status Verified: 2022-01
• Study First Submitted: 2022-01-27
• Study First Submitted QC: 2022-01-27
• Last Update Submitted: 2022-01-27
• Study First Posted: 2022-02-07
• Last Update Posted: 2022-02-07
• Study Start: 2022-04-01
• Primary Completion: 2024-03-31
• Study Completion: 2024-03-31

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 50

Inclusion Criteria

Patients older than 20 undergoing kidney transplantation -

Exclusion Criteria

Patients included in other studies Patients a combined transplant with other donor Patients not eligible to sign an inform consent Patients with primary non-function or those that lost their graft during the first 3 months

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Degree of chimerism	According to the study protocol before and after transplantation in defined intervals up to 3 moths	The fraction of cell free donor DNA will be measured after transplant