Intratracheal antitumor necrosis factor-α antibody attenuates lung tissue damage following cardiopulmonary bypass

The aim of this study is to investigate the protective effect and underlying mechanism of antitumor necrosis factor-α antibody (TNF-α Ab) on lung tissue injury after cardiopulmonary bypass (CPB). Twenty-eight healthy New Zealand white rabbits were randomly divided into four groups. Group I received only an open chest operation. Groups II-IV all received CPB. Furthermore, groups III and IV received post-CPB endotracheal intubation with phosphate buffered saline or TNF-α Ab (2400 pg/kg), respectively. Perioperative blood neutrophil count, TNF-α level, and malondialdehyde (MDA) levels were determined in both the right and left atriums. Lung water content, TNF-α messenger RNA, protein, apoptosis in situ, and pathomorphological changes were also measured. The results show that TNF-α Ab can significantly inhibit leukocyte accumulation, reduce secretion of TNF-α and MDA, decrease lung tissue apoptosis, and attenuate post-CPB pathomorphological changes. TNF-α Ab administration, however, cannot suppress the expression of TNF-α, suggesting that the protective effects of TNF-α Ab originate from inhibiting the numerous biological functions of TNF-α. Intratracheal TNF-α Ab administration demonstrates a notable protective effect against lung injury after CPB.