C4d deposition is correlated with the level of antivimentin antibody in rat kidneys undergoing chronic allograft nephropathy.

AIMS: Antivimentin antibody is often produced as an autoantibody after transplantation. C4d deposition, a marker of humoral immunity during transplantation, is believed to reflect alloantibodies. This study investigated the relationship between C4d deposition and humoral immunity to vimentin among rat kidneys undergoing chronic allograft nephropathy (CAN). METHODS: Fisher 344 rat renal grafts were orthotopically transplanted into Lewis rats following the procedure of Kamada with our modification. All recipients were administered cyclosporine (CsA) (10 mg/kg(-1).d(-1) x 10 d) before being divided into 3 groups of oral treatments: (1) vehicle, (2) CsA (6 mg/kg(-1).d(-1)), and (3) mycophenolate mofetil (MMF; 20 mg/kg(-1).d(-1)). At 4, 8 and 12 weeks after transplantation, the rats were killed, the renal allografts harvested, and the sera collected. Serum creatinine (SCr) was measured and pathologic changes assessed according to the Banff 97 criteria. The antivimentin antibody was quantified by enzyme-linked immunosorbent assay. The deposition of C4d detected by immunofluorescence was analyzed by integrated optical density (IOD). RESULTS: Antivimentin antibody was observed in sera of all transplanted rats. The level of antivimentin antibody (IgGDeltaOD) increased gradually during the development of CAN from 4 weeks. Simultaneously, C4d deposition in peritubular capillaries also progressively strengthened. There was a strong positive correlation between the content of antivimentin antibody and C4d deposition (r = 0.892; P = .000). MMF simultaneously decreased antivimentin antibody formation and C4d deposition. In contrast, CsA had no significant effect. CONCLUSIONS: We demonstrated the production of antivimentin antibodies and the deposition of C4d during the development of CAN. There was a positive correlation between them. Whether humoral immunity to vimentin contributes to C4d deposition is not clear and further studies are needed to elucidate this issue.

Augmentor of liver regeneration ameliorates renal tubular epithelial cell injury after rat liver transplantation.

BACKGROUND: Acute renal insufficiency and dysfunction are common complications after clinical liver transplantation. This study examined whether augmentor of liver regeneration (ALR) played a significant role to ameliorate renal tubular epithelial cell injury after liver transplantation. METHODS: Orthotopic liver transplantation was performed from Sprague-Dawley (SD) to SD rats. Twelve recipients were randomly divided into two groups: ALR group (with recombinated human ALR 100 microg/kg . d intramuscular injection postoperation) versus normal saline-treated group (with the same volume of normal saline injected intramuscularly postoperation). Rats were sacrificed at day 3 posttransplantation. Renal morphological changes in recipients were assessed with light microscopy. The expressions of tumor necrosis factor-alpha (TNF-alpha), proliferating cell nuclear antigen (PCNA) and caspase-3 protein and mRNA in the kidney were evaluated by real-time polymerase chain reaction and immunohistochemical staining. RESULTS: Morphological changes in renal tubular epithelial cells were not significant in either group at day 3 posttransplantation. The intragraft expression of TNF-alpha and caspase-3 was strikingly promoted in the normal saline-treated group and PCNA attenuated compared to the ALR group. CONCLUSION: These data suggested that ALR may play a role to reduce renal damage in liver transplant recipients.