THE PROTEINASE-ANTIPROTEINASE BALANCE IN ALPHA-1-PROTEINASE INHIBITOR-DEFICIENT LUNG-TRANSPLANT RECIPIENTS

We examined the proteinase-antiproteinase balance in the bronchoalveol ar lavage (BAL) fluid from alpha-1-proteinase inhibitor (alpha 1PI)-de ficient lung transplant recipients to determine whether they would der ive benefit from intravenous augmentation therapy with alpha 1PI. BAL fluid from 11 alpha 1PI-deficient lung transplant recipients and eight control subjects was assayed for free neutrophil elastase activity, i mmunoreactive alpha 1PI, and elastase inhibitory capacity. Samples wer e obtained during intervals of health and respiratory illness. BAL flu id from healthy alpha 1PI-deficient lung transplant recipients had min imal or unmeasurable free elastase activity, which was not different f rom that of control subjects. alpha 1PI concentrations in BAL fluid fr om alpha 1PI-deficient lung transplant recipients were reduced when co mpared with those of control subjects. Despite this observation, all b ut one alpha 1PI-deficient patient had the ability to inhibit exogenou s elastase. During respiratory illness, however, three of seven alpha 1PI-deficient lung transplant recipients had measurable free elastase activity, which was inhibited ex vivo by addition of alpha 1PI. We con clude that alpha 1PI-deficient lung transplant recipients demonstrate free elastase activity in BAL fluid during severe lower respiratory tr act inflammation, which is not present during health. Intravenous supp lementation of alpha 1PI-deficient lung transplant recipients with exo genous alpha 1PI during respiratory tract inflammation may be indicate d to inhibit elastase-mediated injury to the transplanted lung.