ENDOTHELIN CONTENT OF BRONCHOALVEOLAR LAVAGE FLUID FROM ALLOTRANSPLANTED PIGS IS INCREASED DURING UNMODIFIED REJECTION

To find a new method for detection of rejection of allotransplanted lu ngs, we studied the endothelin content of bronchoalveolar lavage fluid by radioimmunoassay. Left-sided lung allotransplantation was performe d in pigs. One group of animals received no treatment with immunosuppr essive drugs (rejection group), the other group of animals (treated gr oup) was treated,vith a triple-drug immunosuppressive regimen (cyclosp orine, azathioprine, and methylprednisone), and nontransplanted lungs were controls. The endothelin content in bronchoalveolar lavage fluid was significantly elevated in the group of pigs with unmodified reject ion (29.20 +/- 1.96 pg/ml) compared with that in the immunosuppressed group (15.3 +/- 2.4 pg/ml) and control group (4.27 +/- 1.23 pg/ml). Th e measurements were made from 5, 33, and 11 samples of bronchoalveolar lavage fluid from the rejection, treated, and control groups, respect ively. These results suggest that endothelin content of bronchoalveola r lavage fluid could be a marker of lung allograft rejection.