Endogenous acetylcholine increases alveolar epithelial fluid transport via activation of alveolar epithelial Na,K-ATPase in mice.

The contribution of endogenous acetylcholine to alveolar fluid clearance (AFC) and related molecular mechanisms were explored. AFC was measured in Balb/c mice after vagotomy and vagus nerve stimulation. Effects of acetylcholine chloride on AFC in Kunming mice and Na,K-ATPase function in A549 alveolar epithelial cells also were determined. AFC significantly decreased in mice with left cervical vagus nerve transection compared with controls (48.69 ± 2.57 vs. 66.88 ± 2.64, P ≤ 0.01), which was reversed by stimulation of the peripheral (60.81 ± 1.96, P ≤ 0.01). Compared with control, acetylcholine chloride dose-dependently increased AFC and elevated Na,K-ATPase activity, and these increases were blocked or reversed by atropine. These effects were accompanied by recruitment of Na,K-ATPase α1 to the cell membrane. Thus, vagus nerves participate in alveolar epithelial fluid transport by releasing endogenous acetylcholine in the infusion-induced pulmonary edema mouse model. Effects of endogenous acetylcholine on AFC are likely mediated by Na,K-ATPase function through activation of muscarinic acetylcholine receptors on alveolar epithelia.

[Experimental study of individualized cancer immunotherapy based on dendritic cells against gastric cancer].

OBJECTIVE: To investigate the antitumor effects of cytotoxic T lymphocytes (CTLs) induced by autologous dendritic cells that were inspired by autologous tumor lysates (ATLs-mDCs). METHODS: Primary gastric cancer cells prepared by short-term culture were used as targets. ATLs-mDCs were subjected to activate autologous T cells to generate CTLs. The immunological functions of DCs were evaluated by flow cytometry and by mixed leukocyte response (MLR) assay. The antitumor outcome of tumor antigen specific CTLs was tested by cytotoxicity assay. Concentrations of IL-12 in cultured DCs and INF-gamma in CTLs were measured by ELISA. RESULTS: The expressions of MHC-II, CD80, CD83 and CD86 were significantly up-regulated in ATLs-mDCs, moreover, the ATLs-mDCs obtained the capability of stimulating the proliferation of autologous T cells with high efficiency. The secretion of IL-12 in ATLs-mDCs was significantly higher than that in pure mature DCs (t = 15.47, P < 0.01) and in immature DCs (t = 28.44, P < 0.01). The secretion of INF-gamma in CTLs activated by ATLs-mDCs was significantly higher than that in CTLs by pure mature DCs (t = 4.84, P < 0.05) and in CTLs by immature DCs (t = 13.74, P < 0. 01). The antigen specific cytotoxicity of CTLs induced by ATLs-mDCs was significantly higher against autologous tumor cells [(84 +/- 11)%] than that against two allogeneic tumor cell lines [(19 +/- 7)% and (19 +/- 11)%; t = 54.18 and 56.46, P < 0.01, respectively]. CONCLUSIONS: ATLs-mDCs might mediate the antigen specific CTLs against autologous gastric cancer cells ex vivo with high efficiency.