# Cellular Immunity in Chronic Kidney Disease and Changes After Kidney Transplantation

## TL;DR

The study shows how kidney disease and transplantation affect immune cells in the blood, with some immune components recovering after a transplant.

## Contribution

The study reveals distinct patterns of immune cell changes in CKD and post-transplant patients, particularly highlighting the increase in CD28− T-cells after long-term transplantation.

## Key findings

- Lymphocyte proportions decrease in CKD and hemodialysis but increase after kidney transplantation.
- CD28− T-cell subpopulations significantly increase in long-term transplant recipients compared to hemodialysis patients.
- Regulatory T-cells and NK cells do not fully recover after transplantation.

## Abstract

This study evaluates changes in cellular immunity components, from chronic kidney disease stage V (CKD-V) to long-term transplantation (lKTx). We applied flow cytometry to determine total, CD4+, CD8+, CD28− T-lymphocytes, Natural killer cells (NK) and regulatory T-lymphocytes (Tregs), in peripheral blood of 56 patients with CKD-V, 207 patients on hemodialysis (HD), 149 recently transplanted (rKTx), 26 lKTx patients and 49 healthy volunteers as a control group (CG). Lymphocyte proportion decreased in CKD vs. CG [20.2 (14.4–25.8) vs. 29.7 (24.4–38.1)%, p < 0.001] without further deterioration in HD [19.9 (15.3–23.7)%, p = 0.83 vs. CKD-V] and increased in rKTx [24.7 (20–32.6)%, p < 0.001 vs. HD], and lKTx [25.5 (21.9–35)%, p = 0.16 vs. CG]. Similar kinetics were observed in CD4+ subpopulations, however CD8+ T-cells gradually increased from CG to lKTx. NK remained stable in CKD-V and HD, reduced in rKTx, and marginally increased in lKTx. Tregs gradually declined until HD and suboptimally improved with transplantation. CD28− subpopulations largely increased in lKTx, compared with HD [CD4+CD28−: 12.6 (4.7–27.6) vs. 6 (2.1–13.2)%, p = 0.006, CD8+CD28−: 68.4 (54.4–90.3) vs. 45.5 (28.4–58.9)%, p < 0.001], independently of age for CD8+CD28− (p = 0.33). Cellular immunity subpopulations show significant changes in the spectrum of CKD, with transplantation restoring total lymphocytes and CD4+ T-cells, but not Tregs and NK. LKTx was associated with a large increase in CD28− subpopulations.

Study on cellular immunity in chronic kidney disease and post-kidney transplantation. It presents data from 56 CKD stage V, 207 hemodialysis, 149 recently transplanted, 26 long-term transplanted, and 49 healthy patients. Box plots show lymphocyte and regulatory T cell percentages. Pie charts illustrate CD28 expression in different groups. Scatter plots correlate CD28 expression with age. Flow cytometry was the main research method, and was associated with age, sex, immunosuppression, and CMV status impacts. Research by Lioulios et al. published in Transplant International 2025, DOI: 10.3389/ti.2025.15622. Logos for ESOT and Transplant International are included.