Background; Previously reports showed that CCR7⁺CD8⁺ T cells have suppressive effect on various pathogenic immune cells. The aim of this study is to investigate the regulatory function of CCR7⁺CD8⁺ T cells on allo-reactive effector T cells involved in acute rejection in kidney transplantation.

Methods; We investigated the suppressive effect of CCR7⁺CD8⁺T cells on T cell proliferation and also inflammatory cytokine induced injury on human primary renal tubular epithelial cells (HPRTEpiC) by FACs analysis and ELISA. Also, we compared the proportion of CCR7⁺CD8⁺ T cells in peripheral blood mononuclear cells by FACs analysis between biopsy proven acute rejection (AR)(n=22) and biopsy proven normal histology (NC)(n=16).

Results ;CCR7⁺CD8⁺ T cells significantly decreased the proportion of IFN-g, IL-17/CD4⁺T cells, and production of IL-17 and IL-2 (P<0.05 for each). In contrast, CCR7⁺CD8⁺ T cells increased the production of IL-10/CD4⁺T cells compared to Th17 condition. Second, CCR7⁺CD8⁺ T cells significantly reduced IL-6, IL-8 and CCL20 secretion from HPRTEpiC, which have been induced by inflammatory cytokines or activated T cells. Also, Our results showed that CCR7⁺CD8⁺ T cells significantly reduced IL-17, IFN-g and IL-2 production from T cells co-cultured with HPRTEpiC.Third, ex vivo analysis of PBMCs isolated from kidney transplant recipients (KTRs) with or without acute rejection, the percentage of CCR7⁺CD8⁺ T cells showed significant decrease in the AR group compared to NC group (P<0.05). In contrast, the percentage of CD28^nullCD57⁺ T cell and effector memory CD8 T cell (CD8⁺T_EMRA)increased in the AR group compared to NC group.In peripheral blood from total patients groups, CCR7⁺CD8⁺ T cells was inversely correlated with the CD28^nullCD57⁺ T cell and effector memory CD8 T cell (CD8⁺T_EMRA).

Conclusion; This study suggests that the CCR7⁺CD8⁺T cells effectively regulate effector T cells associated with allograft rejection, which suggests that use of CCR7⁺CD8⁺T cells could be proposed as therapeutic strategy to improve allograft outcome.

CITATION INFORMATION: Chung B, Kim K, Kim B.-M, Doh K, Yang C. CCR7⁺CD8⁺ T Cell Suppresses Effector T Cell Related Allo-Immune Responses in Kidney Transplant Recipients. Am J Transplant. 2017;17 (suppl 3).

« Back to 2017 American Transplant Congress