Immunohistochemical Detection of CD3 and MAC387 Antibodies in the Mesenteric Lymph Nodes and the Small Intestine of 20 Dogs that Died of Canine Parvoviral Enteritis

There is little data on the use of the immunohistochemical method in the observation of the T lymphocytes and macrophages distribution within the mesenteric lymph nodes in canine parvovirus (CPV) enteritis. The virus initially replicates in the systemic lymphoid tissue and causes highest changes in the small intestine. This current study aimed to demonstrate the CD3 and MAC387 antibodies detection and distribution in mesenteric lymph nodes and small intestines in dogs which had positive clinical, pathological, and histological findings of CPV. Twenty dogs that were clinically confirmed on CPV, had been autopsied following onset of death. Tissue samples (lymph nodes and small intestines) from each dog was processed for histology and immunohistochemistry utilizing hematoxylin-eosin and peroxidase/DAB (3,3′-diaminobenzidine) staining methods, respectively. The virus distribution was greatest in the tissue areas of the small intestine and the lymph nodes where the virus had made the most severe tissue damage. The distribution of macrophage was highest in the necrotic areas of the small intestine and the mesenteric lymph nodes. The amount of CD3 positive lymphocytes was greatly reduced in the mesenteric lymph nodes and the lymphoid tissue of the small intestine.