Serum-resistance in Haemophilus parasuis is associated with systemic disease swine
Serum-resistance in Haemophilus parasuis is associated with systemic disease swine
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DOI：
10.1016/j.tvjl.2007.01.016
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发表时间：
2008-03-01
影响因子：
2.2
通讯作者：
Aragon, Virginia
中科院分区：
文献类型：
--
作者：
Cerda-Cuellar, Marta;Aragon, Virginia
副猪嗜血杆菌可引起猪肺炎和全身性疾病，但它也是健康猪上呼吸道的定殖者。这些致病力的差异可能是不同菌株毒力机制不同的结果。由于血清耐药是系统性病原体的常见特征，因此对31株不同临床来源的副猪嗜血杆菌进行了检测，并检测了不同的血清敏感性水平。健康仔猪鼻腔分离株对血清杀菌作用敏感，而全身分离株主要耐药。肺部分离株既有血清敏感株，也有血清抵抗株。有趣的是，耐血清的肺部菌株是从有全身损害的动物身上分离出来的。血清经热处理后杀菌活性消失，说明补体是这一作用的关键因素。对兔和猪血清的敏感性相同，副猪嗜血杆菌特异性抗体的存在不会增加血清对这些菌株的杀伤力。为了试图将血清抵抗力与细菌的表面决定因素联系起来，我们测试了吖啶黄素的凝集作用，但没有发现与血清敏感性有直接联系。结果表明，血清抗性是副猪嗜血杆菌的致病机制之一。(C)2007爱思唯尔有限公司。保留所有权利。
Haemophilus parasuis can cause pneumonia and systemic disease in swine but it is also a coloniser of the upper respiratory tract of healthy pigs. These differences in pathogenicity are probably the result of diverse mechanisms of virulence in different strains. Since serum-resistance is a feature frequently found in systemic pathogens, 31 H. parasuis strains of different clinical origin were tested and a variety of serum susceptibility levels detected. Nasal strains from healthy piglets were sensitive to the bactericidal effect of the serum, while systemic strains were mainly resistant. The pulmonary strains included both serum-sensitive and serum-resistant strains. Interestingly, the serum-resistant pulmonary strains were isolated from animals with systemic lesions. Heat-treatment of the sera abolished the bactericidal activity, indicating that complement is a key factor in this effect. Equivalent susceptibility was observed with rabbit and porcine sera, and the presence of H. parasuis specific antibodies did not increase the killing of the strains by serum. In an attempt to associate serum-resistance to a surface determinant of the bacteria, agglutination in acriflavine was tested but no direct link with serum susceptibility was found. The results indicate that serum-resistance is a virulence mechanism in H. parasuis. (c) 2007 Elsevier Ltd. All rights reserved.