The significance of cytological examination on reperfusion in rat small intestinal transplantation

We examined the cytology of the exudate in preserved intestinal grafts on reperfusion and compared it with the histological findings in rat small intestinal transplantation. The jejunal graft was harvested from the Lewis rat and was preserved in University of Wisconsin solution for 6, 12, 24 and 48 h at 4 °C (n=6, in each group) and was then syngeneically transplanted. On reperfusion, the exudate was collected and studied cytologically. Full thickness biopsies were performed at the end of the preservation and at 30 min after reperfusion for histological examination. Histological examination after reperfusion showed that the crypt layer was preserved until 24 h. However, it was destroyed by 48 h preservation. The cytological findings correlated with the depth of tissue injury shown histologically. The degeneration of villus epithelial cells, the decrease in the content of mucin in both the goblet cells as well as villus cells, and the appearance of crypt cells are all considered to be signs of poor graft viability. Cytological examination is therefore recommended as an effective, non-invasive and real-time method for evaluating graft viability just after reperfusion in small intestinal transplantation.