Shao Lili, Melero Jose, Zhang Nu, Arulanandam Bernard, Baseman Joel, Liu Quanzhong, Zhong Guangming
Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America.
Department of Dermatovenereology, Tianjin Medical University General Hospital, Tianjin, China.
PLoS One. 2017 May 25;12(5):e0177691. doi: 10.1371/journal.pone.0177691. eCollection 2017.
Chlamydia has been detected in the gastrointestinal tracts of both animals and humans. However, the mechanism by which Chlamydia colonizes the gut remains unclear. Chlamydia muridarum is known to spread from the genital to the gastrointestinal tracts hematogenously. The C. muridarum plasmid is a key pathogenic determinant in the mouse upper genital tract although plasmid-deficient C. muridarum is still able to colonize the upper genital tract. We now report that plasmid-deficient C. muridarum exhibits significantly delayed/reduced spreading from the mouse genital to the gastrointestinal tracts. C. muridarum with or without plasmid maintained similar levels in the mouse circulatory system following intravenous inoculation but the hematogenous plasmid-deficient C. muridarum was significantly less efficient in colonizing the gastrointestinal tract. Consistently, plasmid-deficient C. muridarum failed to restore normal colonization in the gastrointestinal tract even after intragastric inoculation at a high dose. Thus, we have demonstrated a plasmid-dependent colonization of C. muridarum in the gastrointestinal tract, supporting the concept that C. muridarum may have acquired the plasmid for adaptation to the mouse gastrointestinal tract during oral-fecal transmission. Since the plasmid is more important for C. muridarum to colonize the gastrointestinal tract than to infect the genital tract, the current study has laid a foundation for further defining the host pathways targeted by the plasmid-encoded or -regulated chlamydial effectors.
衣原体已在动物和人类的胃肠道中被检测到。然而，衣原体在肠道中定殖的机制仍不清楚。已知鼠衣原体可通过血液从生殖道传播至胃肠道。鼠衣原体质粒是小鼠上生殖道中的关键致病决定因素，尽管缺乏质粒的鼠衣原体仍能在上生殖道中定殖。我们现在报告，缺乏质粒的鼠衣原体从小鼠生殖道传播至胃肠道的过程明显延迟/减少。静脉接种后，有或无质粒的鼠衣原体在小鼠循环系统中的水平相似，但缺乏质粒的血源性鼠衣原体在胃肠道定殖的效率明显较低。同样，即使高剂量胃内接种，缺乏质粒的鼠衣原体也无法恢复在胃肠道中的正常定殖。因此，我们证明了鼠衣原体在胃肠道中的定殖依赖于质粒，支持了鼠衣原体可能在粪口传播过程中获得质粒以适应小鼠胃肠道的概念。由于质粒对鼠衣原体在胃肠道定殖比对感染生殖道更重要，本研究为进一步确定质粒编码或调控的衣原体效应子所靶向的宿主途径奠定了基础。
