Yamane C, Yamazaki T, Nakamura S, Matsuo J, Ishida K, Yamazaki S, Oguri S, Shouji N, Hayashi Y, Yoshida Y, Yimin, Yamaguchi H: Amoebal endosymbiont Parachlamydia acanthamoebae Bn9 can grow in immortal human epithelial HEp-2 cells at low temperature; an in vitro model system to study chlamydial evolution. PLoS One 10:e0116486, 2015.