Interaction between human polymorphonuclear leucocytes and Chlamydia trachomatis elementary bodies: electron...

Area of Science:

• Immunology
• Microbiology
• Cell Biology

Background:

• Chlamydia trachomatis is a significant human pathogen.
• Human polymorphonuclear leucocytes (HPMN) are key immune cells involved in combating bacterial infections.
• The interaction between HPMN and Chlamydia trachomatis elementary bodies (EB) is crucial for understanding host defense mechanisms.

Purpose of the Study:

• To investigate the interaction between human polymorphonuclear leucocytes (HPMN) and Chlamydia trachomatis elementary bodies (EB).
• To evaluate the role of specific antibodies in this interaction.
• To assess the chemiluminescent response of HPMN upon exposure to C. trachomatis EB.

Main Methods:

• Incubation of HPMN with purified C. trachomatis EB, with and without specific antibody.
• Electron microscopy to observe cellular interactions and vacuole formation.
• Measurement of HPMN chemiluminescence in response to EB stimulation.

Main Results:

• A 10(3)-fold reduction in viable C. trachomatis EB count was observed after 24h incubation with HPMN.
• Electron microscopy revealed EB attachment, phagocytosis, and vacuole formation within HPMN, with a fuzzy coat observed on EB in the presence of antibody.
• HPMN exhibited a marked chemiluminescent response to EB, significantly higher than controls, with heat-inactivated EB eliciting a reduced response.

Conclusions:

• HPMN are capable of effectively killing Chlamydia trachomatis elementary bodies.
• Specific antibodies enhance the interaction and potentially the killing mechanism.
• The chemiluminescent response of HPMN is indicative of their activation and plays a role in the killing of C. trachomatis EB.