Objective To observe the survival and multiplication of Legionella pneumophila cocultured with Acanthamoeba polyphaga for setting up the laboratory model of such infections. Methods With the ratio of 1∶1000, Acanthamoeba polyphaga and Legionella pneumophila were cocultured under laboratory condition. We investigated the intracellular growth, survival and multiplication of Legionella pneumophila in Acanthamoeba polyphaga in morphological way by using inverted microscopy,electron microscopy and Giemsa staining of the cover glass picking up from the flask. Results Giemsa staining of the cover glass from the culture flask showed that the vacuoles appeared after 8 h coculture, and became more and bigger with the time. After 24 h, Giemsa staining showed that the bacteria started to accumulate within amoeba. In the anaphase of the coculture, the infected amoeba lacked defined organelle structures and was filled with legionella. The electron microscope revealed the survival of legionella in vacuoles of both trophozoites and cysts, showing different phases of binary fission. Conclusions Legionella pneumophila can survive and multiply in Acanthamoeba polyphaga . The results indicated that live amoeba could be a reservoir host for Legionella pneumophila.

Idiopathic pulmonary fibrosis (IPF) is a chronic fatal pulmonary disease characterized by complex illness condition. There is no effective treatment at present except lung transplantation. The comprehensive evaluation is helpful for the management of patients with IPF in hierarchical stages. Therefore, it is very important to evaluate IPF by various independent factors. At present, the commonly used methods for clinical evaluation on IPF include assessment of health-related quality of life, assessment of physiological function, assessment of imaging, assessment of laboratory examination, and multi-dimensional assessment system. However, there are different advantages and disadvantages on diverse evaluation methods for the evaluation of IPF.
Humans ; Idiopathic Pulmonary Fibrosis/diagnosis* ; Quality of Life