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Cyclooxygenase-2 expression in pigs infected experimentally with Mycoplasma hyopneumoniae
M Andrada1, O Quesada-Canales1, A Suárez-Bonnet1
1Unit of Veterinary Histology and Pathology, Institute for Animal Health, Veterinary School, Universidad de Las Palmas de Gran Canaria, 35413 Arucas, Gran Canaria, Spain.
Abstract:
Porcine enzootic pneumonia, primarily caused by Mycoplasma hyopneumoniae (Mh), is a contagious disease characterized by catarrhal bronchointerstitial pneumonia. Previous studies have evaluated immunohistochemically the distribution of Mh, different cellular populations and cytokines during Mh-induced pneumonia. Cyclooxygenase (COX)-2 is overexpressed during inflammatory responses by different cell types in the lung. The aim of this study was to elucidate the possible role of COX-2 in the pathogenesis of porcine enzootic pneumonia. COX-2 protein was detected by immunohistochemistry in formalin-fixed, paraffin wax-embedded lung tissues from 10 pigs infected experimentally with Mh. Ten pigs were inoculated intranasally with Mh and killed in pairs weekly from 1 to 5 weeks post inoculation. Three Mh-free pigs were taken as controls. Bronchial and bronchiolar epithelial cells, bronchial submucosal glands and a small number of macrophages in the bronchoalveolar exudate expressed COX-2. COX-2 protein was always associated with areas of pneumonia and expression was minimal in lungs from control pigs. These results suggest that COX-2 plays a role in the pathogenesis of Mh-infection.
Insights
Cyclooxygenase (COX)-2 is involved in porcine enzootic pneumonia, a disease caused by Mycoplasma hyopneumoniae (Mh). COX-2 protein expression was observed in infected pig lungs, suggesting its role in the disease process.
Area of Science:
- Veterinary Pathology
- Mycoplasma hyopneumoniae Research
- Inflammation and Immunology
Background:
- Porcine enzootic pneumonia, caused by Mycoplasma hyopneumoniae (Mh), is a significant respiratory disease in pigs.
- Inflammatory responses in the lungs involve the overexpression of Cyclooxygenase (COX)-2 by various cell types.
- Previous research has examined Mh distribution and cellular responses in pneumonia.
Purpose of the Study:
- To investigate the potential role of COX-2 in the pathogenesis of Mycoplasma hyopneumoniae-induced pneumonia in pigs.
- To determine the localization and expression patterns of COX-2 in experimentally infected porcine lungs.
Main Methods:
- Experimental infection of pigs with Mycoplasma hyopneumoniae (Mh).
- Collection and processing of lung tissues from infected and control pigs at weekly intervals (1-5 weeks post-inoculation).
- Immunohistochemical detection of COX-2 protein in formalin-fixed, paraffin-embedded lung tissues.
Main Results:
- COX-2 protein expression was detected in bronchial and bronchiolar epithelial cells, bronchial submucosal glands, and macrophages within the bronchoalveolar exudate.
- COX-2 expression was significantly higher in lungs affected by pneumonia compared to control pigs.
- Expression of COX-2 was minimal in lungs from Mh-free control pigs.
Conclusions:
- The findings suggest that COX-2 plays a role in the inflammatory pathogenesis of Mycoplasma hyopneumoniae infection in pigs.
- COX-2 expression is associated with pneumonic lesions in the porcine lung.
- Further research could explore therapeutic strategies targeting COX-2 in porcine respiratory diseases.
