Detection of peripheral blood and bronchoalveolar lavage fluid lymphocytes in rat lung transplantation for early diagnosis of rejection.

Abstract

Left lung transplantation was performed in two combinations of rat strains. In group 1, lung grafts were rejected within 7 day postoperatively, and in group 2, grafts were rejected within 18 day postoperatively. The histological appearance of rejection was classified into 4 stages, and lymphocytes from peripheral blood (PB) and bronchoalveolar lavage fluid (BALF) were collected at each stage. In group 1, a significant decrease in the number of lymphocytes in PB was observed as the rejection progressed, whereas the number of lymphocytes in PB increased slightly in group 2. The number of total cells in BALF increased significantly as the rejection progressed in both groups. A marked increase in the value of spontaneous blastogenesis (SB) was observed in stage 2 in BALF lymphocytes, whereas that in PB lymphocytes was found to increase after stage 3 in both groups. The ratio of T-helper/T-nonhelper did not change significantly in PB lymphocytes in both groups. On the other hand, a significant decrease in the value of T-helper/T-nonhelper (less than 1.0) was observed in BALF at stage 3 and 4 in both groups. These results show that the studies of BALF lymphocytes were very useful for early diagnosis of rejection in lung transplantation.