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Updated: Mar 17, 2026
A Human Fallopian Tube Model for Investigation of C. trachomatis Infections
Published on: August 11, 2012
MRI as a Novel In Vivo Approach for Assessing Structural Changes of Chlamydia Pathology in a Mouse Model
Catherine D G Hines1, Shubing Wang2, Xiangjun Meng1
1Department of Translational Imaging Biomarkers, MRL (West Point, PA), Merck & Co., Inc., Kenilworth, New Jersey, United States of America.
Abstract:
Chlamydia trachomatis is among the most prevalent of sexually transmitted diseases. While Chlamydia infection is a reportable event and screening has increased over time, enhanced surveillance has not resulted in a reduction in the rate of infections, and Chlamydia infections frequently recur. The development of a preventative vaccine for Chlamydia may be the only effective approach for reducing infection and the frequency of pathological outcomes. Current vaccine research efforts involve time consuming and/or invasive approaches for assessment of disease state, and MRI presents a clinically translatable method for assessing infection and related pathology both quickly and non-invasively. Longitudinal T2-weighted MRI was performed over 63 days on both control or Chlamydia muridarum challenged mice, either with or without elementary body (EB) immunization, and gross necropsy was performed on day 65. A scoring system was developed to assess the number of regions affected by Chlamydia pathology and was used to document pathology over time and at necropsy. The scoring system documented increasing incidence of pathology in the unimmunized and challenged mice (significantly greater compared to the control and EB immunized-challenged groups) by 21 days post-challenge. No differences between the unchallenged and EB immunized-challenged mice were observed. MRI scores at Day 63 were consistently higher than gross necropsy scores at Day 65, although two of the three groups of mice showed no significant differences between the two techniques. In this work we describe the application of MRI in mice for the potential evaluation of disease pathology and sequelae caused by C. muridarum infection and this technique's potential for evaluation of vaccines for Chlamydia.
Insights
Chlamydia trachomatis infections are common and recurring, necessitating a vaccine. Magnetic Resonance Imaging (MRI) offers a non-invasive method to assess Chlamydia pathology and evaluate vaccine efficacy in mice.
Area of Science:
- Medical Imaging
- Infectious Diseases
- Vaccinology
Background:
- Chlamydia trachomatis is a prevalent sexually transmitted infection with increasing rates despite enhanced surveillance.
- Recurrent Chlamydia infections and associated pathology highlight the need for effective preventative strategies, such as vaccination.
- Current methods for assessing Chlamydia pathology in vaccine research are often invasive and time-consuming.
Purpose of the Study:
- To evaluate the utility of longitudinal T2-weighted MRI for non-invasively assessing Chlamydia muridarum infection and related pathology in a mouse model.
- To investigate the potential of MRI as a clinically translatable method for evaluating Chlamydia vaccine efficacy.
- To develop and apply a scoring system for quantifying Chlamydia-induced pathology over time using MRI.
Main Methods:
- Longitudinal T2-weighted MRI was performed on mice challenged with Chlamydia muridarum over 63 days.
- Mice were either immunized with elementary bodies (EB) or received no immunization.
- A standardized scoring system was used to quantify pathology, with gross necropsy performed on day 65 for comparison.
Main Results:
- Unimmunized, challenged mice showed significantly increased pathology by day 21 compared to control and EB-immunized groups.
- No significant differences in pathology were observed between unchallenged and EB-immunized, challenged mice.
- MRI scores at day 63 generally correlated with gross necropsy scores at day 65, indicating MRI's potential for pathology assessment.
Conclusions:
- MRI is a promising non-invasive tool for evaluating Chlamydia muridarum infection and pathology in vivo.
- This MRI technique can potentially streamline the assessment of Chlamydia vaccine candidates.
- The study demonstrates MRI's utility in tracking disease progression and evaluating the impact of immunization in Chlamydia infection models.
