Urethral inflammation in male chimpanzees caused by ureaplasmas and Chlamydia trachomatis

Area of Science:

• Urology
• Microbiology
• Primate Research

Background:

• Non-gonococcal urethritis (NGU) is a common infection in men.
• The microbial etiology of NGU is not fully understood, with Ureaplasma species being potential contributors.
• Chimpanzees serve as a valuable model for studying human urogenital infections.

Purpose of the Study:

• To investigate the role of Ureaplasma species in causing urethritis.
• To assess the interaction between Ureaplasma and Chlamydia trachomatis in the male urethra.
• To evaluate the pathogenic potential of Ureaplasma in a primate model.

Main Methods:

• Urethral inoculation of male chimpanzees with Ureaplasma species and/or Chlamydia trachomatis.
• Monitoring for clinical signs of urethritis, including inflammation and polymorphonuclear leukocyte (PMNL) response.
• Microbial culture and serological testing to confirm infections and immune responses.

Main Results:

• Ureaplasma species alone caused urethral inflammation and a PMNL response in chimpanzees.
• Co-infection with Ureaplasma and C. trachomatis suggested a delay or suppression of the chlamydial response by Ureaplasma.
• C. trachomatis infection alone resulted in the most pronounced urethral inflammation and PMNL response.
• Ureaplasmas were transiently detected in the oropharynx and conjunctiva without causing inflammation.
• Mycoplasma genitalium was ruled out as a cause of urethritis due to a lack of antibody response.

Conclusions:

• Ureaplasma species can induce urethritis in male chimpanzees.
• Ureaplasma may modulate the host response to C. trachomatis in the male urogenital tract.
• The chimpanzee model is useful for studying the pathogenesis of urethritis.