Differences in Tfh Cell Response between the Graft and Spleen with Chronic Allograft Nephropathy

Abstract

The aim of this study was to investigate follicular helper T (Tfh) cell response and its difference between renal graft and spleen in a rat renal transplantation model undergoing chronic allograft nephropathy (CAN). Orthotopical kidney transplantations were performed on Fischer (F344) rats and transplanted to Lewis rats, using syngeneic Lewis–Lewis grafts as controls. Tissue samples were collected at 8 weeks posttransplantation. The status of Tfh cell response was assessed by measuring the levels of transcription factor B-cell lymphoma 6 (Bcl-6), interleukin-21 (IL-21), chemokine receptor type 5 (CXCR5), and B-cell-activating factor belonging to the TNF family (BAFF). Tfh cell response was upregulated in both renal graft and spleen of the CAN group compared to the control group. However, Tfh cell response of the spleen was weaker than that of the graft, which was possibly related to the upregulation of splenic Treg activation. Also, the difference between two tissues was partially associated with the different expressions of tristetraprolin (TTP)/IL-10. Our data help improve our understanding of the role of Tfh cell response in the body with CAN and may provide a valuable clue for better treatment of CAN.