IFNy+ and IFNy- Treg subsets with stable and unstable Foxp3 expression in kidney transplant recipients with good long-term graft function

Karina Trojan; Christian Unterrainer; Mostafa Aly; Li Zhu; Rolf Weimer; Nuray Bulut; Christian Morath; Gerhard Opelz; Volker Daniel

doi:10.1016/j.trim.2016.10.003

IFNy+ and IFNy- Treg subsets with stable and unstable Foxp3 expression in kidney transplant recipients with good long-term graft function

Transpl Immunol. 2016 Oct 29:S0966-3274(16)30124-1. doi: 10.1016/j.trim.2016.10.003. Online ahead of print.

Authors

Karina Trojan¹, Christian Unterrainer², Mostafa Aly³, Li Zhu⁴, Rolf Weimer⁵, Nuray Bulut⁶, Christian Morath⁷, Gerhard Opelz⁸, Volker Daniel⁹

Affiliations

¹ Transplantation-Immunology, Institute of Immunology, University Hospital Heidelberg, Im Neuenheimer Feld 305, 69120 Heidelberg, Germany. Electronic address: [email protected].
² Transplantation-Immunology, Institute of Immunology, University Hospital Heidelberg, Im Neuenheimer Feld 305, 69120 Heidelberg, Germany. Electronic address: [email protected].
³ Transplantation-Immunology, Institute of Immunology, University Hospital Heidelberg, Im Neuenheimer Feld 305, 69120 Heidelberg, Germany. Electronic address: [email protected].
⁴ Transplantation-Immunology, Institute of Immunology, University Hospital Heidelberg, Im Neuenheimer Feld 305, 69120 Heidelberg, Germany. Electronic address: [email protected].
⁵ Department of Internal Medicine, University of Giessen, Klinikstrasse 33, D-35385 Giessen, Germany. Electronic address: [email protected].
⁶ Department of Internal Medicine, University of Giessen, Klinikstrasse 33, D-35385 Giessen, Germany. Electronic address: [email protected].
⁷ Department of Nephrology, University of Heidelberg, Heidelberg, Germany. Electronic address: [email protected].
⁸ Transplantation-Immunology, Institute of Immunology, University Hospital Heidelberg, Im Neuenheimer Feld 305, 69120 Heidelberg, Germany. Electronic address: [email protected].
⁹ Transplantation-Immunology, Institute of Immunology, University Hospital Heidelberg, Im Neuenheimer Feld 305, 69120 Heidelberg, Germany. Electronic address: [email protected].

PMID: 27989714
DOI: 10.1016/j.trim.2016.10.003

Abstract

Background: Treg are a heterogenous cell population. In the present study we attempted to identify Treg subsets that might contribute to stable and good long-term graft function.

Method: Lymphocyte and Treg subsets were studied in 136 kidney transplant recipients with good long-term graft function and in 52 healthy control individuals using eight-color-fluorescence flow cytometry. Foxp3 TSDR methylation status was investigated in enriched IFNy+ and IFNy- Treg preparations using high resolution melt analysis.

Results: Compared with healthy controls, patients showed strong associations of IFNy secreting Helios+ and Helios- Treg with Treg that co-expressed perforin and/or CTLA4 (CD152; p<0.01). Moreover they showed associations of IFNy-Helios+ Treg with Treg that produced TGFβ and/or perforin and of IFNy-Helios- Treg with TGFβ production (all p<0.01). Only in patients, but not in healthy controls, were IFNy- Helios+ and Helios- Treg associated with higher CD45+, CD3+, (CD4+), CD19+ lymphocyte counts (p<0.001). In addition IFNy-Helios+ Treg were associated with CD16+56+ lymphocytes (p<0.001). Enriched IFNy- Treg from female but not male patients showed an association of Foxp3 methylation with higher total Treg and higher Helios+IFNy-, CXCR3+Lselectin+ (CD183+CD62L+), CXCR3-Lselectin+ and CD28+HLADR+ Treg subsets (p<0.01). Enriched IFNy+ Treg from male patients showed an association of demethylated Foxp3 with total Treg and IL10-TFGβ+ Treg counts, and in enriched IFNy- Treg an association of methylated Foxp3 with APO1/FasR+FasL+ (CD95+CD178+) Treg (p<0.01).

Conclusions: Kidney recipients with good long-term graft function possess IFNy+ and IFNy- Treg with stable and unstable Foxp3 expression in the blood. They co-express CD28, HLADR, CTLA4, CXCR3, Lselectin, TGFβ, perforin and FasL and might contribute to the establishment and maintenance of good long-term graft function.

Keywords: Foxp3 TSDR methylation; Good long-term graft function; IFNy+ Treg; IFNy− Treg; Kidney transplant recipients; Stable Foxp3 expression; Unstable Foxp3 expression.