Ito A, Matsuo J, Nakamura S, Yoshida A, Okude M, Hayashi Y, Sakai H, Yoshida M, Takahashi K, Yamaguchi H. Amoebal endosymbiont Protochlamydia induces apoptosis to human immortal HEp-2 cells. PLoS One. 2012, 7(1):e30270.