P388 Mycoplasma genitalium-reactive antibodies in serum and urethral specimens of persistently infected men
Year: 2021
Type: conference-abstract
Abstract: Background Mycoplasma genitalium (MG) is a sexually transmitted pathogen associated with acute and chronic genital tract infection in men and women. Although MG-reactive antibodies have been detected in cervicovaginal specimens of infected women, antibodies at the site of infection in men have not been characterized. We compared MG-reactive antibodies in serum and urethral swabs of MG positive and negative men with urethritis to better understand the immunopathogenesis of MG. Methods Paired urethral swab and serum specimens were collected from men enrolled in a double-blinded study comparing azithromycin and doxycycline for treatment of non-gonococcal urethritis conducted from 2007–2011. Among 22 MG-positive men, antibody reactivity to MG was determined by immunoblot for specimens collected at enrollment and the last MG-positive visit (15–86 days later). Paired specimens from 13 MG-negative men served as controls. Results In serum specimens, MG-reactive antibodies were detected in all 22 MG-positive men. In 10 men, increasing reactivity to the MgpB and MgpC immunodominant adherence proteins occurred over time. In comparison, sera from MG-negative men reacted poorly (7/13) or not at all (6/13) to these proteins. In urethral specimens, MG-specific antibody was detected in 22/22 MG-positive men demonstrating these antibodies are present at the site of infection. Surprisingly, antibody reactivity in urethral specimens decreased over time in 12/19 patients despite the persistence of antibodies in serum and MG in the urethra. Among MG-negative men, 8/13 had detectable MgpB/MgpC reactive antibody in urethral specimens but reactivity was very low. Conclusion Serum antibodies to MG correlated well with infection status, but local antibodies did not. Despite the persistence of MG in the urethra, antibody reactivity at the site of infection diminished over time. Whether this reduced reactivity reflects reduced bacterial load over time, or whether diminution of local antibodies contributes to persistent infection should be examined in future studies.
Source: Poster presentations
Language: English
Subfield: Microbiology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W3182291462