OBJECTIVE: To explore the influences of rapamycin (RAPA) upon the cytokine changes of activated spleen ãäT lymphocytes and lung tissue macrophages in acute lung injury of mice induced by lipopolysaccharide (LPS).METHODS: A total of 24 healthy male C57BL/6 mice, 6-8 weeks old, were randomly divided into phosphate buffered saline (PBS), LPS, RAPA and LPS + RAPA groups. Acute lung injury was induced by a single intratracheal instillation of LPS in mice. And spleen ãäT lymphocytes and lung macrophages were purified by immunomagnetic beads at Day 1. The purified spleen ãäT lymphocytes and lung macrophages were adjusted to 10(6) cell/ml. And 24-well plates were used for 4 groups. Each group were further separated with spleen ãäT lymphocytes alone, lung tissue macrophages alone and co-culturing. Supernatant fluid was collected after 24 hours. The expressions of IFN-ã and TNF-á were analyzed by ELISA (enzyme-linked immunosorbent assay). And the expressions of mRNA were analyzed by real-time quantitative PCR (polymerase chain reaction).RESULTS: The total cells numbers and lymphocytes numbers of bronchoalveolar lavage fluid were significantly higher in LPS group than those in PBS and LPS + RAPA groups (P < 0.05). And the level of IFN-ã was significantly higher in LPS group than that in PBS, RAPA and LPS + RAPA groups by co-culture (P < 0.05). The level of TNF-á was significantly higher in LPS group than that in RAPA gand LPS + RAPA groups by co-culture (P < 0.05). However, the mRNA of IFN-ã was higher in LPS group than that in PBS and RAPA groups (P < 0.05).CONCLUSION: RAPA inhibits the secretion levels of IFN-ã and TNF-á in spleen ãäT lymphocytes and lung tissue macrophages in acute lung injury of mice induced by LPS.
Acute Lung Injury Animals