Purpose
Prolonged cold ischemia has been shown to be an important factor in the development of post-transplant renal dysfunction. The exact mechanisms have not been completely defined. The expression of ICAM-1 (CD-54) in rat kidneys stored at 0, 4, 12,
24
and
48 hours in University of Wisconsin (UW) solution was studied in an attempt to correlate ischemia time with increased immunogenicity of the graft.
Methods
Kidneys from male Lewis rats were perfused with UW solution, removed and bathed in UW solution at 4℃ for 4, 12, 24, and 48 hours respectively. For the evaluation of expression of ICAM-1, immunohistochemical staining, Western blotting and RT-PCR
were
performed.
Results
Immunohistochemical staining in normal non-ischemic kidneys revealed that glomerular capillaries expressed ICAM-1 but that tubular cells did not. The preserved kidneys were analyzed with immunohistochemistry, Western blotting and
semi-quantitative
RT-PCR and showed increased transcription and express
ion of ICAM-1 in the cortex of the kidney. This expression reached a maximum at 24 hours and declined at 48 hours. The ICAM-1 protein expression in the preserved kidney cortex was increased at 4 hours (1.68±0.60 fold of control kidneys,
(p=0.06)),
12
hours (2.38±0.90 fold, (p=0.02)), 24 hours (3.70±1.29 fold, (p=0.01)), and 48 hours (2.00±0.54 fold, (p=0.01)). The mRNA expression (the ratio of ICAM-1/GAPDH) in preserved kidneys cortex relative to control kidneys was increased at 4 hours
(1.19±0.14 fold of control kidneys), 12 hours (1.38±0.16 fold),24 hours (1.77±0.29 fold), and 48 hours (1.19±0.12 fold) (p<0.05 for all time points).
Conclusion
We conclude that cold preservation of rat kidneys in UW solution induces increasing levels of ICAM-1 cell surface expression and gene transcription. This increase in adhesion molecule expression can be a contributing factor in the development of
post-transplant renal dysfunction by increasing the immunogenicity of the graft.
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