Contribution of T lymphocytes to rat renal ischemia/reperfusion injury

This study aimed to elucidate the early involvement of T lymphocytes in renal ischemia/reperfusion injury. Athymic nude rats (F344/N_Jcl-nu) and control F344/Jcl were subjected to 45 min unilateral renal ischemia. To determine whether the observed differences might be derived from the T lymphocyte presence, T lymphocytes from the spleens of F344/Jcl were injected into F344/N_Jcl-nu via tail vein at the initiation of reperfusion. Immunohistochemical analysis was performed for CD3, the proliferative cell nuclear antigen (PCNA), vimentin, and E-cadherin. T lymphocytes were obtained from the green fluorescent protein transgenic (GFP) rats, and transplanted to F344/N_Jcl-nu 10 min before reperfusion. The animals were euthanized 15 min after reperfusion. F344/N_Jcl-nu showed less retention of both Cr and BUN at 24 and 48 h after reperfusion, compared with F344/Jcl. F344/N_Jcl-nu received T lymphocyte transplantation showed significantly higher retention of both Cr and BUN 24, 48, and 72 h after reperfusion than those without T lymphocyte. A rapid infiltration of T lymphocytes into proximal tubular epithelial cells and tubular lumen was observed using T lymphocytes with green fluorescent protein. In contrast, T lymphocytes were observed with much less frequency 24 h after ischemia. The number of PCNA-positive proximal tubular cells 24 h after the initiation of reperfusion was significantly smaller in the T lymphocyte transplantation group compared with the non-transplantation group. The vimentin positivity and cytoplasmic staining of E-cadherin were also more prominent in the transplantation group. These findings demonstrate a rapid renal T lymphocyte infiltration, which propagate renal functional deterioration.