Defective Treg response in acute kidney injury was caused by a reduction in TIM-3+ Treg cells

Immunol Invest. 2019 Jan;48(1):27-38. doi: 10.1080/08820139.2018.1493497. Epub 2018 Jul 9.

Abstract

Background: Despite years of research, the treatment of acute kidney injury (AKI) remains a significant challenge. Animal studies presented causal links between elevated regulatory T cell (Treg) response and better prognosis in AKI. Previous studies in mice and humans showed that TIM-3+ Treg cells were more potent than TIM-3- Treg cells. In this study, we investigated the role of TIM-3 in Treg in AKI patients.

Methods: Peripheral blood from AKI patients and healthy controls were gathered, and TIM-3+ Treg subset was examined.

Results: Compared to healthy controls, the AKI patients presented a significant upregulation in the frequency of circulating CD4+CD25+ T cells; however, the majority of this increase was from the CD4+CD25+TIM-3- subset, and the frequency of CD4+CD25+TIM-3+ T cells was downregulated in AKI patients. In both healthy controls and AKI patients, the CD4+CD25+TIM-3+ T cells expressed higher levels of Foxp3, and were more potent at expressing LFA-1, LAG-3, CTLA-4, IL-10 and TGF-β. In addition, the CD4+CD25+TIM-3+ T cells from both healthy controls and AKI patients presented higher capacity to suppress CD4+CD25- T cell proliferation than the CD4+CD25+TIM-3- T cells. Interestingly, the total CD4+CD25+ T cells from AKI patients presented significantly lower inhibitory capacity than those from healthy controls, indicating that the low frequency of CD4+CD25+TIM-3+ T cells was restricting the efficacy of the Treg responses in AKI patients.

Conclusions: We demonstrated that TIM-3 downregulation impaired the function of Treg cells in AKI. The therapeutic potential of CD4+CD25+TIM-3+ T cells in AKI should be investigated in future studies.

Keywords: Acute kidney injury; Tim-3; Treg.

MeSH terms

  • Acute Kidney Injury / immunology*
  • Aged
  • Animals
  • Cell Proliferation
  • Cells, Cultured
  • Female
  • Forkhead Transcription Factors / metabolism
  • Hepatitis A Virus Cellular Receptor 2 / metabolism*
  • Humans
  • Immune Tolerance
  • Interleukin-10 / metabolism
  • Lymphocyte Activation
  • Lymphocyte Function-Associated Antigen-1 / metabolism
  • Male
  • Mice
  • Middle Aged
  • T-Lymphocytes, Regulatory / immunology*
  • Transforming Growth Factor beta / metabolism

Substances

  • FOXP3 protein, human
  • Forkhead Transcription Factors
  • HAVCR2 protein, human
  • Hepatitis A Virus Cellular Receptor 2
  • Lymphocyte Function-Associated Antigen-1
  • Transforming Growth Factor beta
  • Interleukin-10