中文摘要：

嗜肺军团菌是一种生活在人工水环境中的条件性致病菌，环境条件对该菌的存活和胞内增殖具有重要的影响．本文用作者建立的军团菌-四膜虫模型，研究了空调水池水、Fe^3＋和感染温度3种关键性环境因子对嗜肺军团菌在嗜热四膜虫宿主细胞内增殖的影响．结果发现，尽管空调水中Fe^3＋浓度大大低于培养基中的Fe^3＋浓度，但适合嗜肺军团菌在嗜热四膜虫宿主胞内的存活和增殖；感染缓冲液中的Fe^3＋能够被嗜热四膜虫富集，并被胞内的军团菌加以利用，缓冲液中浓度0．05×10^-6的Fe^3＋即可显著促进胞内军团菌的增殖，但0．1×10^-6和0．5×10^-6的Fe^3＋促进军团菌胞内增殖的效果差异不显著；较高的温度对军团菌的胞内增殖也有明显促进作用，35℃时，即使感染复数等于10，军团菌也可进行胞内复制扩增，并最终裂解宿主细胞．图7表1参17

英文摘要：

Effect of three pivotal environmental factors, cooling tower water, ferric ion and temperature, on the intracellular proliferation of the fateful opportunistic pathogen Legionella pneumophila within ciliate host was investigated by the Legionella- Tetrahyrnena model built previously. The results showed that the cooling tower water, although containing much lower concentration of Fe^3＋ than medium, was more suitable for intracellular survival and proliferation of L. pneumophila compared to PYG -buffer even at 10 of MOI. The results also demonstrated that the ciliate host could enrich Fe^3＋ from infection buffer, thus providing enough Fe^3＋ for intracellular multiplication of L. pneumophila. The enriched Fe^3＋ promoted intracellular proliferation remarkably even at concentration of O. 05 ×10^-6 in the buffer. On the other hand, the intracellular proliferation rate of the bacteria was similar at 0. 1 ×10^-6 and 0. 5 ×10^-6 of Fe^3＋ in the buffer. Higher temperature also promoted intracellular multiplication of L. pneumophila. At 35℃, L. pneumophila could proliferate within the host cells even at 10 of MOI, which finally led to lysis of host cells. Fig 7, Tab 1, Ref 17