Spinal Cord Medulloepithelioma in a Cat.

A 13-month-old, neutered, male, domestic shorthair cat was referred with a history of progressive paraparesis, proprioceptive ataxia, and lumbar spinal pain. Neurological examination revealed non-ambulatory paraparesis consistent with L4-S1 myelopathy. Magnetic resonance of the thoracolumbar spinal cord identified a dorsal intradural extramedullary space-occupying lesion extending from L5 to L6. It was homogeneously hyperintense in T2-weighted imaging and isointense in T1-weighted imaging and exhibited marked and homogeneous contrast enhancement in the T1-weighted post-contrast imaging. The removed tissue was composed of neoplastic cells arranged as pseudostratified or multilayered trabecular and tubular structures, supported by internal and external limiting PAS-positive membranes. The neoplastic cells were immunoreactive for vimentin and NSE and negative for GFAP, Olig2, synaptophysin, PCK, S-100, NeuN, and nestin. The Ki-67 nuclear labeling index was up to 90%. The tumor was consistent with the diagnosis of medulloepithelioma, which is most frequently reported as an intraocular tumor. The morphological and immunohistochemical features of the tumor showed remarkable concordance with most human medulloepitheliomas. This is the first spinal cord medullopethelioma report in a cat, with the clinical, neuroradiological, histological, and immunohistochemical findings being described.

Endometrial expression of antimicrobial peptides as markers of subclinical endometritis in mares.

BACKGROUND: Endometritis is a major cause of subfertility in mares. Multiparous old mares are more susceptible to developing endometritis given that ageing is associated with an altered immune response and with inadequate physiological uterine clearance after breeding, which can lead to degenerative changes in the endometrium. Molecules such as antimicrobial peptides (AMPs) have been proposed as endometritis markers in the equine species. STUDY DESIGN: Cross-sectional. OBJECTIVES: To investigate the endometrial expression of defensin-beta 4B (DEFB4B), lysozyme (LYZ) and secretory leukocyte peptidase inhibitor (SLPI) genes in mares either affected or not by subclinical endometritis, due to the role of these AMPs in the immune response to bacteria and inflammatory reactions. METHODS: Endometrial biopsy for histopathological and gene expression examinations was performed on 26 mares. The inclusion criteria for the normal mare group (NM, N = 7) were 2-4 years of age, maiden status, no clinical signs of endometritis and a uterine biopsy score of I, while for mares affected by subclinical endometritis (EM, N = 19) the inclusion criteria were 10-22 years of age, barren status for 1-3 years, no clinical signs of endometritis and a uterine biopsy score between IIA and III. RESULTS: A significantly higher expression of LYZ (NM: 0.76 [1.84-0.37] vs. EM: 2.78 [5.53-1.44], p = 0.0255) and DEFB4B (NM: 0.06 [0.11-0.01] vs. EM: 0.15 [0.99-0.08], p = 0.0457) genes was found in endometritis mares versus normal mares. Statistically significant moderate positive correlations were found between the level of expression of LYZ gene and both the age (r = 0.4071, p = 0.039) and the biopsy grade (r = 0.4831, p = 0.0124) of the mares. MAIN LIMITATIONS: The study investigated a limited number of genes and mares, and the presence/location of the proteins coded by these genes was not confirmed within the endometrium by IHC. CONCLUSIONS: If the results of this study are confirmed, LYZ and DEFB4B genes can be used as markers to identify mares that are affected by subclinical endometritis.

Evaluation of species-specific polyclonal antibodies to detect and differentiate between Neospora caninum and Toxoplasma gondii.

Neosporosis and toxoplasmosis are major causes of abortion in livestock worldwide, leading to substantial economic losses. Detection tools are fundamental to the diagnosis and management of those diseases. Current immunohistochemistry (IHC) tests, using sera raised against whole parasite lysates, have not been able to distinguish between Toxoplasma gondii and Neospora caninum. We used T. gondii and N. caninum recombinant proteins, expressed in Escherichia coli and purified using insoluble conditions, to produce specific polyclonal rabbit antisera. We aimed to develop species-specific sera that could be used in IHC on formalin-fixed, paraffin-embedded (FFPE) tissue sections to improve the diagnosis of ruminant abortions caused by protozoa. Two polyclonal rabbit sera, raised against recombinant proteins, anti-Neospora-rNcSRS2 and anti-Toxoplasma-rTgSRS2, had specificity for the parasite they were raised against. We tested the specificity for each polyclonal serum using FFPE tissue sections known to be infected with T. gondii and N. caninum. The anti-Neospora-rNcSRS2 serum labeled specifically only N. caninum-infected tissue blocks, and the anti-Toxoplasma-rTgSRS2 serum was specific to only T. gondii-infected tissues. Moreover, tissues from 52 cattle and 19 sheep previously diagnosed by lesion profiles were tested using IHC with our polyclonal sera and PCR. The overall agreement between IHC and PCR was 90.1% for both polyclonal anti-rNcSRS2 and anti-rTgSRS2 sera. The polyclonal antisera were specific and allowed visual confirmation of protozoan parasites by IHC, but they were not as sensitive as PCR testing.