Senescence and Uremia Effects in Circulating T Cells Diverge in TREG Population and Cause T Cell Shift to a Memory Profile.
1Renal Transplantation Service, University of Sao Paulo, Sao Paulo, Brazil
2Department of Geriatrics, University of Sao Paulo, Sao Paulo, Brazil
3Laboratory of Immunology, InCor, University of Sao Paulo, Sao Paulo, Brazil
Meeting: 2017 American Transplant Congress
Abstract number: D17
Keywords: B cells, Kidney transplantation, Lymphocytes, T cells
Session Information
Session Name: Poster Session D: Cellular & Bone Marrow Transplantation Session II
Session Type: Poster Session
Date: Tuesday, May 2, 2017
Session Time: 6:00pm-7:00pm
Presentation Time: 6:00pm-7:00pm
Location: Hall D1
Elderly kidney transplant recipients(EKtx) have higher malignancies and infections rates, but lower acute rejection incidence. Senescence seems to result in shift to memory profile and uremia in premature immunological aging. Understanding combined senescence and uremia effects in immune system can improve EKtx immunosuppression individualization.
We analyzed senescence and uremia effects in circulating lymphocyte subpopulations, comparing healthy young(HY)(n=14,26±2y), healthy elderly(n=15,79±7y), young kidney transplant recipients(n=17,36±7y) and EKtx(n=27,65±3y) before transplant. We analyzed the following phenotypes: TEMRA(CD4+CCR7–CD45RA+), naive(CD4+CCR7+CD45RA+), central memory(TCM)(CD4+CCR7+CD45RA–) and effector memory (TEM)(CD4+CCR7–CD45RA–) T cells, regulatory T cells (TREG)(CD4+CD25+CD127–FOXP3+CD39+), naïve(CD19+CD24intCD38int), memory(CD19+CD24hiCD38lo) and regulatory(BREG)(CD19+CD24HiCD38Hi) B cells. Percentages and absolute lymphocyte counts were compared by Mann Whitney and Two-Way ANOVA.
Senescence and uremia correlated with lower absolute counts for B and T lymphocytes, affecting many subpopulations with memory, naïve and regulatory profiles. Senescence and uremia resulted in higher percentage of memory subsets, the former in TCM [F(1,72)=6.2, p=0.02, [eta]2=0.08] and the latter in TEM[F(1,72)=4.7, p=0.03, [eta]2=0.06]. We found opposing effects on Treg: higher percentage in senescence[F(1,72)=4.4, p=0.04, [eta]2=0.06] and lower in uremia [F(1,72)=5.7, p=0.02, [eta]2=0.07]. Senescence and uremia presented additive effects on absolute cell counts, lowering total T and B cell subpopulations, but without interaction. Combined effect of senescence and uremia also resulted in higher BREG percentage [EKtx-10(7-14)% of CD19 vs. HY-6(5-8)% of CD19, p=0.02].
Senescence and uremia are responsible for global decrease of absolute lymphocyte counts and percentage shift to T memory profile, but opposing effects on TREG percentage. Combination of senescence and uremia induces cumulative effects on lymphocyte counts, but do not interact. These encourage tailoring EKTx immunosuppression, favoring a selective control of memory T cells whith preservation of TREGs and BREGs.
CITATION INFORMATION: Freitas G, Fernandes M, Agena F, Jabuul O, Coelho V, Lemos F, Ramos F, Triboni A, David-Neto E, Galante N. Senescence and Uremia Effects in Circulating T Cells Diverge in TREG Population and Cause T Cell Shift to a Memory Profile. Am J Transplant. 2017;17 (suppl 3).
To cite this abstract in AMA style:
Freitas G, Fernandes M, Agena F, Jabuul O, Coelho V, Lemos F, Ramos F, Triboni A, David-Neto E, Galante N. Senescence and Uremia Effects in Circulating T Cells Diverge in TREG Population and Cause T Cell Shift to a Memory Profile. [abstract]. Am J Transplant. 2017; 17 (suppl 3). https://atcmeetingabstracts.com/abstract/senescence-and-uremia-effects-in-circulating-t-cells-diverge-in-treg-population-and-cause-t-cell-shift-to-a-memory-profile/. Accessed May 17, 2025.« Back to 2017 American Transplant Congress