Role of crosslinked protein in lung injury following total. body irradiation and bone marrow transplantation

The aberrant protein crosslinks formation during lung injury as results total body irradiation (TBI) and bone marrow transplantation (BMT) therapy has been examined as apossible contributory factor in organ or tissue pathogenesis. Female C3HeB/ FeJ mice were used for an experimental animal. Carbon monoxide uptake (V-CO) was measured at 1, 2, 3, 4 and 5 months after TBI at respective doses of 12, 14, 16 and 18 Gy 16 h prior to syngeneic BMT. Also as a measure of aberrant protein crosslinking in the inured tissues, transglutaminase (TGase)-activities and crosslinked protein were examined along with thrombin, a protease known to activate TGases. Reductions of V-CO were detected following TBI and BMT. Activities of thrombin and TGase 1, and crosslinked protein in bronchoalveolar lavage (BAL) fluid of the mice 1 wk after TBI at 12 Gy and BMT were identified and found to be elevated in the treated animals. These findings suggest that elevated levels of crosslinked proteins and TGase I in the bronchoalveolar larvage during the lung injury could have enhanced the organ pathogenesis following TBI and BMT.