Department of Microbiology and Immunology, University of South Alabama Mobile, AL, USA.
Front Cell Infect Microbiol. 2012 Aug 15;2:108. doi: 10.3389/fcimb.2012.00108. eCollection 2012.
Burkholderia pseudomallei and Burkholderia mallei, the etiologic agents of melioidosis and glanders, respectively, cause severe disease in humans and animals and are considered potential agents of biological warfare and terrorism. Diagnosis and treatment of infections caused by these pathogens can be challenging and, in the absence of chemotherapeutic intervention, acute disease is frequently fatal. At present, there are no human or veterinary vaccines available for immunization against these emerging/re-emerging infectious diseases. One of the long term objectives of our research, therefore, is to identify and characterize protective antigens expressed by B. pseudomallei and B. mallei and use them to develop efficacious vaccine candidates. Previous studies have demonstrated that the 6-deoxy-heptan capsular polysaccharide (CPS) expressed by these bacterial pathogens is both a virulence determinant and a protective antigen. Consequently, this carbohydrate moiety has become an important component of the various subunit vaccines that we are currently developing in our laboratory. In the present study, we describe a reliable method for isolating CPS antigens from O-polysaccharide (OPS) deficient strains of B. pseudomallei; including a derivative of the select agent excluded strain Bp82. Utilizing these purified CPS samples, we also describe a simple procedure for covalently linking these T-cell independent antigens to carrier proteins. In addition, we demonstrate that high titer IgG responses can be raised against the CPS component of such constructs. Collectively, these approaches provide a tangible starting point for the development of novel CPS-based glycoconjugates for immunization against melioidosis and glanders.
类鼻疽伯克霍尔德菌和鼻疽伯克霍尔德菌分别是类鼻疽和鼻疽的病原体，它们可导致人类和动物罹患严重疾病，被认为是生物战剂和生物恐怖主义的潜在制剂。这些病原体引起的感染的诊断和治疗可能具有挑战性，并且在没有化学治疗干预的情况下，急性疾病通常是致命的。目前，尚无用于预防这些新发/再发传染病的人类或兽医疫苗。因此，我们研究的长期目标之一是鉴定和表征类鼻疽伯克霍尔德菌和鼻疽伯克霍尔德菌表达的保护性抗原，并利用它们开发有效的疫苗候选物。先前的研究表明，这些细菌病原体表达的 6-脱氧-庚烷荚膜多糖（CPS）既是毒力决定因素，也是保护性抗原。因此，该碳水化合物部分已成为我们目前在实验室中开发的各种亚单位疫苗的重要组成部分。在本研究中，我们描述了一种从 O-多糖（OPS）缺陷型类鼻疽伯克霍尔德菌菌株中分离 CPS 抗原的可靠方法，包括一种被选定的制剂排除菌株 Bp82 的衍生物。利用这些纯化的 CPS 样品，我们还描述了一种将这些 T 细胞非依赖性抗原共价连接到载体蛋白的简单程序。此外，我们证明可以针对此类构建体的 CPS 成分引发高滴度 IgG 反应。总之，这些方法为开发针对类鼻疽和鼻疽的新型 CPS 基糖缀合物提供了切实可行的起点。
