Department of Veterinary Pathobiology, University of Peradeniya, Sri Lanka.
Acta Trop. 2011 Oct-Nov;120(1-2):72-81. doi: 10.1016/j.actatropica.2011.06.016. Epub 2011 Jul 7.
No data is available in the world literature on serum anti-rhinosporidial antibody levels in animals, and as far as we aware this is the first report. Although rhinosporidiosis in farm and domestic animals has been widely reported from other countries, rhinosporidiosis in animals has not been reported in Sri Lanka, though this country has the highest world-wide prevalence of human rhinosporidiosis on a unit-population basis. Serum IgG titres in 6 species of Sri Lankan animals (buffalo, cat, cattle, dog, goat, horse; total 291) were assayed by the Immuno blot (dot-ELISA) method on nitrocellulose paper and were compared with serum IgG titres in normal Sri Lankan human subjects (total 211) in different geographical areas, and in human Sri Lankan patients with rhinosporidiosis as reference values (total 36). Sensitization to rhinosporidial antigen(s) was detected in all 6 species of animals and the highest titres (1/3200) were found in cats, and free-grazing horses. Cattle showed higher levels of antibody than buffaloes. The titres in these animals are compared with world reports on overt rhinosporidiosis in these species, and with titres in normal Sri Lankan humans. Human, but not animal titres showed variations compatible with the regional prevalence of rhinosporidiosis. The variations in titres in animals especially horses, were probably more related to their mode of feeding, while in humans the titres in normal persons were probably related to the rhinosporidial-endemicity of their respective regions. No conclusions from sero-positivity in animals could be made regarding the absence of reports on rhinosporidiosis as an overt disease in these Sri Lankan animal species but the possibility of a genetically-determined insusceptibility to rhinosporidiosis in Sri Lanka, is considered. Rhinosporidium seeberi-specific PCR positive reactions were obtained with nasal scrapings from cattle that microscopically showed PAS+ bodies that were compatible with rhinosporidial sporangia. Sequence-analysis of the reactions products from five positive R. seeberi-specific PCR samples (four in this study and 1 in a previous study) gave results confirmatory of R. seeberi.
目前世界范围内尚无有关动物血清抗鼻孢子菌抗体水平的数据，据我们所知，这是首次报告。尽管其他国家已广泛报道了农场和家养动物中的鼻孢子菌病，但在斯里兰卡尚未有此类报道，尽管该国的人口基础上全球范围内人类鼻孢子菌病的患病率最高。我们采用免疫印迹（斑点酶联免疫吸附试验）法在硝酸纤维素纸上检测了来自斯里兰卡 6 种动物（水牛、猫、牛、狗、山羊、马；共 291 份血清）的 IgG 效价，并与来自不同地理区域的正常斯里兰卡人类受试者（共 211 人）和作为参考值的人类鼻孢子菌病患者（共 36 人）的血清 IgG 效价进行了比较。结果显示，所有 6 种动物均对鼻孢子菌抗原产生了致敏反应，猫和自由放养的马的效价最高（1/3200）。牛的抗体水平高于水牛。将这些动物的效价与这些物种中明显的鼻孢子菌病的世界报道以及与正常的斯里兰卡人类进行了比较。人类的效价而非动物的效价显示出与鼻孢子菌病区域性流行相一致的变化。动物尤其是马的效价变化可能与其喂养方式更为相关，而人类中正常人的效价可能与其各自地区的鼻孢子菌病流行情况有关。鉴于这些斯里兰卡动物物种中未报告明显的鼻孢子菌病，但动物血清呈阳性反应，因此不能对此做出任何结论，但认为在斯里兰卡，鼻孢子菌病的易感性可能是由遗传决定的。我们从显微镜下显示 PAS+ 体的牛的鼻拭子中获得了与 Rhinosporidium seeberi 特异性 PCR 阳性反应，这些 PAS+ 体与鼻孢子菌的孢子囊相吻合。对来自五份阳性 R. seeberi 特异性 PCR 样本（本研究中的四份和之前研究中的一份）的反应产物进行序列分析的结果证实了 R. seeberi 的存在。
