Related Experiment Videos
Alveolar macrophage response to experimentally induced ornithosis
Abstract:
Effects of two strains of the agent of ornithosis upon alveolar macrophages of mice were compared. Macrophages were obtained by lavages of the lower respiratory tract. Experimental mice were intranasally infected with 100 LD50 of strain P 89 and strain Stanglová, respectively. Up to the culmination of the disease (from 6th to 8th day in P 89 and from 5th to 8th day in Stanglová), the number of harvested macrophages increased. The phagocytic index soon reached values around 40% (P 89) and 25% (Stanglová). Basophilic and eosinophilic macrophages increased in volume and their nuclear as well as plasma membranes became disrupted. A tendency of alveolar macrophages to fuse and form syncytial elements and sporadically, rosets, was observed. All cells in the lavage went through the same changes. Histological examination has shown initial changes in epithelial cells of bronchi and development of pneumonia after fusion of peribronchial leucocytic infiltrates. By employing the above described technique, no great changes in the quality of the effects of either strain P 89 or Stanglová were found. A slight difference was observed only in the degree of alveolar macrophage stimulation and in the onset of symptoms.
Insights
Comparing two ornithosis strains, researchers found similar effects on mouse alveolar macrophages, with slight differences in stimulation and symptom onset. Both strains increased macrophage numbers and altered cell structures, leading to pneumonia.
Area of Science:
- Immunology
- Microbiology
- Pathology
Background:
- Ornithosis is an infectious disease caused by Chlamydia psittaci.
- Alveolar macrophages play a crucial role in lung immunity.
- Understanding strain-specific effects is vital for disease management.
Purpose of the Study:
- To compare the effects of two distinct ornithosis strains (P 89 and Stanglová) on mouse alveolar macrophages.
- To investigate cellular changes and immune responses in the lower respiratory tract.
Main Methods:
- Intranasal infection of mice with specific doses of P 89 and Stanglová strains.
- Collection of alveolar macrophages via lower respiratory tract lavage.
- Analysis of macrophage number, phagocytic index, cellular morphology, and fusion.
- Histological examination of lung tissues.
Main Results:
- Both strains increased the number of harvested alveolar macrophages up to disease culmination.
- Phagocytic index reached approximately 40% for P 89 and 25% for Stanglová.
- Macrophages exhibited increased volume, membrane disruption, fusion into syncytia, and rosette formation.
- Histology revealed epithelial cell changes in bronchi and pneumonia development.
Conclusions:
- Both P 89 and Stanglová strains induce significant alterations in alveolar macrophages.
- A slight difference was noted in the degree of macrophage stimulation and symptom onset between the strains.
- The observed cellular changes contribute to the pathogenesis of ornithosis-induced pneumonia.