Chlamydia muridarum Induction of Glandular Duct Dilation in Mice

Abstract

Although Chlamydia-induced hydrosalpinx in women and mice has been used as a surrogate marker for tubal infertility, the medical relevance of nontubal pathologies, such as uterine horn dilation, developed in mice following chlamydial infection remains unclear. We now report that the uterine horn dilation correlates with glandular duct dilation detected microscopically following Chlamydia muridarum infection. The dilated glandular ducts pushed the uterine horn lumen to closure or dilation and even broke through the myometrium to develop extrusion outside the uterine horn. The severity scores of uterine horn dilation observed macroscopically correlated well with the number of cross sections of the dilated glandular ducts counted under microscopy. Chlamydial infection was detected in the glandular epithelial cells, potentially leading to inflammation and dilation of the glandular ducts. Direct delivery of C. muridarum into the mouse uterus increased both uterine horn/glandular duct dilation and hydrosalpinx. However, the chlamydial plasmid, which is essential for the induction of hydrosalpinx, was not required for the induction of uterine horn/glandular duct dilation. Screening 12 strains of mice for uterine horn dilation following C. muridarum infection revealed that B10.D2, C57BL/10J, and C57BL/6J mice were most susceptible, followed by BALB/cJ and A/J mice. Deficiency in host genes involved in immune responses failed to significantly alter the C. muridarum induction of uterine horn dilation. Nevertheless, the chlamydial induction of uterine horn/glandular duct dilation may be used to evaluate plasmidindependent pathogenicity of Chlamydia in susceptible mice.

Parenteral vaccination protects against transcervical infection with Chlamydia trachomatis and generate tissue-resident T cells post-challenge

“…This type of pathology was also observed in other recent studies. 6,48,49 Pathology in the oviducts, more specifically hydrosalpinx, is a known pathological marker for infertility in mice. Others have, however, also observed a correlation between infertility and uterine horn and glandular duct dilation, 49 and the TC model (using C.t.)…”

Rectal administration of a chlamydial subunit vaccine protects against genital infection and upper reproductive tract pathology in mice

“…The uterine horn dilation was chronic and therefore likely caused by glandular duct dilation, which may occur first, pushing into the uterine horn lumen causing uterine horn lumenal blockades at multiple sites and leading to extensive uterine horn lumenal dilation as previously reported following C . muridarum infection [ 48 ]. Although hydrosalpinx is an important pathologic marker of Chlamydia - induced infertility in mice [ 6 , 48 – 50 ], none of the immunized and control mice in the studies reported here developed any overt hydrosalpinx as assessed by visual examination.…”

IL-6-mediated signaling pathways limit Chlamydia muridarum infection and exacerbate its pathogenicity in the mouse genital tract

“…The sections were stained with hematoxylin and eosin (H&E) as described elsewhere [6]. The H&E stained sections were scored for severity of inflammation and dilation based on the modified schemes established previously [6, 39, 40]. Scoring for inflammatory cell infiltrates (at the chronic stage of infection, the infiltrates mainly contain mononuclear cells): 0, no significant infiltration; 1, infiltration at a single focus; 2, infiltration at two to four foci; 3, infiltration at more than four foci; and 4, confluent infiltration.…”