Kidney allograft rejection is associated with an imbalance of B cells, regulatory T cells and differentiated CD28-CD8+ T cells: analysis of a cohort of 1095 graft biopsies.

Introduction: The human immune system contains cells with either effector/memory or regulatory functions. Besides the well-established CD4+CD25hiCD127lo regulatory T cells (Tregs), we and others have shown that B cells can also have regulatory functions since their frequency and number are increased in kidney graft tolerance and B cell depletion as induction therapy may lead to acute rejection. On the other hand, we have shown that CD28-CD8+ T cells represent a subpopulation with potent effector/memory functions.

Antibody-mediated allograft rejection is associated with an increase in peripheral differentiated CD28-CD8+ T cells - Analyses of a cohort of 1032 kidney transplant recipients.

Background: CD28-CD8+ T cells represent a differentiated CD8+ T cell subset that is found to be increased in various conditions associated with chronic antigenic stimulation such as aging, chronic viral infections, autoimmune diseases, cancers, and allotransplantation.

Methods: Using multivariate models, we analyzed a large cohort of 1032 kidney transplant patients in whom 1495 kidney graft biopsies were performed concomitant with a peripheral blood leukocyte phenotyping by flow cytometry. We investigated the association between the level of CD28-CD8+ T cells in the blood and the diagnosis of graft rejection according to the recent Banff classification of renal allograft pathology.

Efficient Expansion of Human Granzyme B-Expressing B Cells with Potent Regulatory Properties.

Granzyme B-expressing B cells have been shown to be an important regulatory B cell subset in humans. However, it is unclear which subpopulations of B cells express GZMB under normal conditions and which protocols effectively induce ex vivo expansion of GZMB B cells. We found that in the peripheral blood of normal individuals, plasmablasts were the major B cell subpopulation that expressed GZMB.

CXCR5PD1ICOS Circulating T Follicular Helpers Are Associated With Donor-Specific Antibodies After Renal Transplantation.

Donor-specific anti-HLA antibodies (DSAs) are a major risk factor associated with renal allograft outcomes. As a trigger of B cell antibody production, T follicular helper cells (Tfhs) promote DSA appearance. Herein, we evaluated whether circulating Tfhs (cTfhs) are associated with the genesis of antibody-mediated rejection.