Impact of cold preservation on leukocyte adhesion to the transplanted rat lung.

Little is known about leukocyte migration in the early phase after ischemia-reperfusion injury. Recently, there has been much focus on in vivo visualization of cell kinetics. Previously, we established a method for the in vivo visualization of leukocyte circulation using a Green Fluorescent Protein transgenic rat. Herein, we developed a simplified rat heterotopic lung transplantation model that can be mastered by beginners within a few weeks. Using this system, we studied the impact of preservation on adhesion of circulating leukocytes to the transplanted lung. The graft of a fresh group was compared with that of a preserved group. Morphological and immunohistochemical analyses were also performed. We successfully visualized few adherent leukocytes in the fresh graft, whereas adherent cells were attached in the preserved graft within a few minutes. In conclusion, the prolonged cold preservation time promotes leukocyte adhesion, resulting in increased microvascular injury after lung transplantation.