Matté Yasmin Ampese, Baldasso Débora Zini, Rezende Mariana Antunes, Lui Jean Francisco Maldaner, Seibel Ana Clara, Guizzo João Antônio, Frandoloso Rafael, Kreutz Luiz Carlos
Graduate Program in Bioexperimentation, Laboratory of Advanced Microbiology and Immunology, School of Agricultural Sciences, Innovation and Business, University of Passo Fundo, 99052-900 Passo Fundo, RS, Brazil.
AFK Imunotech, Passo Fundo, RS, Brazil.
Vet World. 2025 Apr;18(4):755-762. doi: 10.14202/vetworld.2025.755-762. Epub 2025 Apr 7.
is an obligatory intracellular bacterium associated with equine proliferative enteropathy (EPE), which significantly impacts equine health. Despite its clinical relevance, epidemiological and diagnostic approaches for this infection in horses have remained underexplored. This study aimed to evaluate the humoral immune response in horses immunized with an experimental vaccine for and to determine the occurrence of anti- antibodies in horses from southern Brazil using the flow cytometry antibody test (FCAT).
A total of 12 horses were immunized with an experimental vaccine containing inactivated and adjuvants. Blood samples were collected on day 0 (D0) and every 7 days until day 35 (D35) to monitor the antibody response using FCAT. In addition, serum samples from 79 horses from the North and Northwest regions of Rio Grande do Sul were tested to determine the occurrence of anti- antibodies. The FCAT protocol was optimized for equine samples, and a cut-off fluorescence threshold was determined using Receiver Operating Characteristic curve analysis.
FCAT demonstrated high accuracy, with a sensitivity of 100% and specificity of 92% at a fluorescence cut-off of ≥15%. Immunization triggered a robust humoral response, with a significant increase in fluorescence from day 7 to day 35. In the occurrence analysis, 26% of the horses tested positive for anti- antibodies. The highest occurrence was observed in females (35.8%) and horses aged 16-22 years (50%).
This study provided evidence that infection is relatively common among horses in southern Brazil. FCAT was a sensitive and specific diagnostic tool for detecting anti- antibodies in horses. The findings highlight the need for better diagnostic and preventive measures to control EPE in equine populations.
是一种与马增生性肠炎（EPE）相关的专性胞内细菌，对马的健康有重大影响。尽管其具有临床相关性，但马感染这种病菌的流行病学和诊断方法仍未得到充分探索。本研究旨在评估用针对的实验性疫苗免疫的马的体液免疫反应，并使用流式细胞术抗体检测（FCAT）确定巴西南部马匹中抗抗体的出现情况。
总共12匹马用含有灭活和佐剂的实验性疫苗进行免疫。在第0天（D0）和每7天采集血样，直到第35天（D35），以使用FCAT监测抗体反应。此外，对来自南里奥格兰德州北部和西北部地区的79匹马的血清样本进行检测，以确定抗抗体的出现情况。FCAT方案针对马样本进行了优化，并使用受试者工作特征曲线分析确定了荧光截止阈值。
FCAT显示出高准确性，在荧光截止值≥15%时，灵敏度为100%，特异性为92%。免疫引发了强烈的体液反应，从第7天到第35天荧光显著增加。在出现情况分析中，26%的测试马匹抗抗体呈阳性。在雌性（35.8%）和16 - 22岁的马匹（50%）中观察到最高出现率。
本研究提供了证据表明在巴西南部的马匹中感染相对常见。FCAT是检测马抗抗体的灵敏且特异的诊断工具。这些发现突出了在马群中控制EPE需要更好的诊断和预防措施。
