Cytokine gene expression in kidney allograft biopsies after donor brain death and ischemia-reperfusion injury using in situ reverse-transcription polymerase chain reaction analysis

Background. This study focuses on the cytokine genes expression after brain-death, ischemia-reperfusion injury, and during allograft rejection. Methods. A total of 49 needle core biopsies from kidney transplant recipients, performed before and during transplantation procedures were studied. The first biopsy was taken during procurement of the organ, the second after cold ischemia, and the third after approximately 30 min of reperfusion. We also assessed 34 allograft biopsies obtained during acute rejection. Tubular and glomerular expression of interferon (IFN)-gamma, transforming growth factor (TGF)-beta l, platelet-desired growth factor-B (PDGF-B), interleukin (IL)-2, IL-6, IL-10 mRNA was analyzed with reverse-transcription polymerase chain reaction (RT-PCR) in situ technique, which allows to detect a few copies of the target gene without destruction of the tissue architecture. Results. Compared with normal kidney tissue from living donor, high gene expression of IFN-gamma, TGF-beta 1, PDGF-B, IL-2, IL-6, and IL-10 was detected in all procurement specimens. After reperfusion gene expressions of IL-2, IL-6, and IL-10 were significantly upregulated in renal tubules compared to biopsies taken after cold ischemia. The gene expression of IFN-gamma, TGF-01, and PDGF-B remained stable after organ procurement, during cold ischemia, and after reperfusion. Gene expression of IFN-gamma, IL-2, IL-6, IL-10, and PDGF-B in procurement biopsies, as well as in those taken after cold ischemia and reperfusion, were significantly higher than during the period of acute rejection. Conclusion. The data presented herein strongly point out the importance of the immunological and morphological injury that occurs before and during transplantation. The increase of inflammatory response after brain death is important for further stimulation of the immune response and long-term kidney survival.