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Detection of Abnormal Prion Protein by Immunohistochemistry
Published on: May 5, 2023
Matrix metalloproteinase expression in sheep with listerial meningoencephalitis
Fatma İlhan1, Yavuz Ulusoy, Mehmet Halıgür
1Department of Pathology, Faculty of Veterinary Medicine, Yüzüncü Yıl University, 65080 Kampus, Van, Turkey. fatmasayn@hotmail.com
Abstract:
Matrix metalloproteinases (MMPs) have been implicated in the pathogenesis of several central nervous system (CNS) diseases. In this study, we investigated the presence of Listeria monocytogenes antigens and detected the expression of MMP-9 and MMP-7 in the brains of 22 sheep with clinical signs and histopathological findings characteristic of listerial meningoencephalitis. Archived sections from the brainstem, cerebrum, and cerebellum were stained for immunohistochemistry. L. monocytogenes antigens were located mainly in the cytoplasm of neutrophils and some macrophages and/or extracellularly within microabscesses of the brainstem. MMP-9 was mainly immunolocalised in the endothelial cells, microglial cells, and neurons especially in inflammatory areas. MMP-7 immunoreactivity was detected in perivascular cuffs, microglial cells, and only a few neurons. Overall, immunohistochemistry in formalin-fixed, paraffin-embedded tissues is a useful tool for the diagnosis of encephalitic listeriosis caused by L. monocytogenes, and MMP-9 and MMP-7 may contribute to the pathogenesis of listerial meningoencephalitis.
Insights
This study found Listeria monocytogenes antigens and matrix metalloproteinases (MMPs) in sheep brains with meningoencephalitis. MMP-9 and MMP-7 may play a role in this central nervous system disease.
Area of Science:
- Veterinary Pathology
- Neuroscience
- Immunology
Background:
- Matrix metalloproteinases (MMPs) are linked to central nervous system (CNS) disease pathogenesis.
- Listerial meningoencephalitis is a significant CNS disease in sheep.
Purpose of the Study:
- To investigate Listeria monocytogenes antigens and MMP-9/MMP-7 expression in ovine listerial meningoencephalitis.
- To evaluate immunohistochemistry as a diagnostic tool for encephalitic listeriosis.
Main Methods:
- Immunohistochemistry was performed on brain sections (brainstem, cerebrum, cerebellum) from 22 sheep with listerial meningoencephalitis.
- Detection of L. monocytogenes antigens, MMP-9, and MMP-7 expression.
Main Results:
- L. monocytogenes antigens were found in neutrophils, macrophages, and extracellularly in microabscesses.
- MMP-9 was localized in endothelial cells, microglia, and neurons, particularly in inflammatory areas.
- MMP-7 immunoreactivity was observed in perivascular cuffs, microglia, and some neurons.
Conclusions:
- Immunohistochemistry is effective for diagnosing L. monocytogenes encephalitic listeriosis.
- MMP-9 and MMP-7 expression suggests their involvement in the pathogenesis of listerial meningoencephalitis.
