Detection of equine herpesvirus-1 in the fetal membranes of aborted equine fetuses by immunohistochemical and in-situ hybridization techniques.

This research article focuses on the detection of equine herpesvirus-1 (EHV-1) in aborted horse fetuses using immunohistochemical and in-situ hybridization techniques. The results indicate a correlation between the presence of the virus and certain abnormal conditions in the fetal membranes.

Methodology

• The scientists worked with formalin-fixed, paraffin wax-embedded fetal membranes from 76 equine abortion cases.
• The fetal membranes were analyzed immunohistochemically, a process that uses antibodies to detect the presence of specific proteins in a sample.
• This method was used to try and detect EHV-1 antigens, proteins produced by the virus that trigger an immune response.
• Out of the 76 cases, 11 had been previously confirmed to have EHV-1 through viral isolation in tissue culture, immunohistochemical examination, or both.

Findings

• From the 11 EHV-1-positive fetal membranes, five tested positive in the immunohistochemical examination and three tested positive on in-situ hybridization, a technique that uses a labeled complementary DNA or RNA strand to locate a specific DNA or RNA sequence in a tissue.
• The virus detection signals were found in areas indicating abnormal conditions: vacuolar degeneration, desquamation of chorionic epithelium, mild lympho-histiocytic vasculitis, placentitis, and unusually increased metabolic activity in mesenchymal cells located in the villi of the fetal membranes.
• The detected virus appeared to be present in trophoblastic cells, monocytes and occasionally endothelial cells.

Significance

• This study represents the first report of EHV-1 antigen and nucleic acid detection in trophoblasts of fetal membranes from spontaneous cases of equine abortion.
• The correlations drawn between the virus presence and abnormal conditions in the fetal membranes could provide insights for future research and treatment.