Memory B cells and anti-HLA sensitization in kidney transplant candidates

Alloreactive Memory B Lymphocytes and Anti-HLA Sensitization in Kidney Transplantation

Observational University Hospital, Rouen · NCT07011238

This project will test whether analyzing memory B cells in adults with anti-HLA antibodies who are waiting for a kidney transplant can help predict their risk of antibody-related rejection.

Quick facts

Study typeObservational
Enrollment51 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity Hospital, Rouen Academic / other
Drugs / interventionsrituximab
Locations1 site (Rouen)
Trial IDNCT07011238 on ClinicalTrials.gov

What this trial studies

This observational project will characterize the phenotypic, functional and clonal diversity of pre-existing alloreactive memory B lymphocytes in kidney transplant candidates with anti-HLA antibodies. Adult patients on the Rouen University Hospital transplant waiting list will be stratified by incompatible graft rate (IGR) into hyperimmunized (IGR ≥85%), immunized (IGR 50–85%) and naïve (IGR <50%) groups. Blood samples will be analyzed to define Bmem clonality, surface markers and antibody specificities to try to distinguish potentially pathogenic from non-pathogenic responses. Comparing these groups aims to link intensity of prior HLA exposure to features of the alloreactive B cell repertoire that could inform post-transplant humoral risk.

Who should consider this trial

Good fit: Adults (≥18) followed at Rouen University Hospital on the national kidney transplant waiting list who have detectable anti-HLA antibodies and meet one of the defined IGR categories are the intended participants.

Not a fit: Patients without detectable anti-HLA antibodies, those whose sensitization is only from transfusions, people who recently received B-cell–depleting therapy (e.g., rituximab), and individuals not followed at Rouen University Hospital are unlikely to benefit or be eligible.

Why it matters

Potential benefit: If successful, this work could help clinicians better predict which sensitized patients face higher risk of antibody-mediated rejection and tailor prevention and monitoring strategies.

How similar studies have performed: Prior studies have identified alloreactive memory B cells in sensitized patients, but using those findings to reliably predict clinical transplant risk is still novel and not yet proven.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Age ≥ 18 years
* Rouen University Hospital patient monitored in the Nephrology and Kidney Transplantation Department, registered on the national kidney transplant waiting list
* Carrier of HLA antibodies, including at least anti-HLA2, identified during the last screening
* Notion of classic immune-promoting events including at least one previous transplant or pregnancy, or absence of a known immune-promoting event (naïve patient group)
* Incompatible graft rate (IGR)

  * IGR ≥ 85% (hyperimmunized patient group with anti-HLA polyreactivity) or
  * IGR between 50% and 85% (immunized patient group with a more restricted repertoire of HLA reactivities) or
  * IGR \< 50% (naïve patient group with no known history of immune-promoting events)
* Person who has read and understood the information letter and does not object Not participating in the study
* Affiliation to a social security scheme

Exclusion Criteria:

* Patients who have received rituximab in the previous year (B-cell depleting therapy)
* Patients undergoing an HLA desensitization protocol using plasmapheresis and/or rituximab
* Patients with an active infection
* Persons deprived of their liberty by an administrative or judicial decision or persons placed under judicial protection/guardianship or curatorship

Where this trial is running

Rouen

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Kidney TransplantB lymphocytes
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.