Peripheral and Intrarenal B Cell Study in Antibody Mediated Transplant Rejection : Phenotypic and Transcriptional Study, Study of Reactivity (B-KiMi)

Assistance Publique - Hôpitaux de Paris

Status: Not yet enrolling

Conditions: Antibody Mediated Rejection After Kidney Transplantation

Treatments: Biological: Stool collection; Biological: Blood collection; Biological: Piece of kidney removal

Study type: Observational

Funder types: Other

Identifiers

NCT07134491

APHP250908

Details and patient eligibility

About

Humoral rejection of kidney transplants is responsible for a large number of kidney graft losses in a context of increasing shortage.

Although it has been established that it is largely mediated by the alloreactive B lymphocyte, anti-B therapies are only partially effective.

The mechanisms behind the loss of tolerance are also poorly understood, and the triggers of rejection remain to be elucidated.

During this study, patients admitted for kidney graft biopsy for suspicion of rejection will be included ; patients presenting non inflammatory biopsies will be studied as controls. B cells will be extracted and cultured. Their antibodies will be studied along with reactivity towards HLA, non HLA targets and the gut microbiome. The same study will be led for late rejections needing graft removal : B cells extraction, culture, antibodies reactivity testing. Controls will be graft removal for non inflammatory causes. In both cases hight throughput sequencing the immunoglobulin genes will be performed.

Enrollment: 45 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Adult kidney transplant recipients admitted for biopsy or graft removal in the participating nephrology departments.
• Patient participation agreement and signed consent form
• Affiliation to a health insurance system

Exclusion criteria

• Confounding factor of renal inflammation: acute or recurrent pyelonephritis, BK virus nephropathy
• Pregnant or breast-feeding women
• Persons under legal protection

Trial design

45 participants in 2 patient groups

kidney biopsy or graft removal for rejection

Description:

Renal transplant recipients with suspicion of rejection or undergoing kidney biopsy or graft removal

Treatment:

Biological: Piece of kidney removal

Biological: Blood collection

Biological: Stool collection

kidney biopsy or graft removal for reasons other than rejection

Description:

Renal transplant recipients with undergoing kidney graft removal or biopsy for reansons other than rejection

Treatment:

Biological: Piece of kidney removal

Biological: Blood collection

Biological: Stool collection