Development of antibodies to capsule of carbapenem resistant Klebsiella pneumonia

描述（由申请人提供）：耐碳青霉烯类肺炎克雷伯菌（CR-Kp）分离株正在世界范围内出现，包括在美国。疾病预防控制中心报告，患病率从2001年的1.6%上升到2011年的10.4%。CR-Kp主要引起肺炎、败血症和尿路感染。大多数患者在卫生保健相关环境中获得这种病原体，但在社区健康人群中也观察到CR-Kp感染。一个问题是，许多CR-Kp分离株保留了完全的毒力，甚至经常对氨基糖苷产生耐药性。二线储备抗生素如环素或多粘菌素疗效低或毒性大，特别是对肾功能受损的患者。因此，侵袭性Cr-Kp感染的死亡率很高，在50-80%之间。目前还没有针对革兰氏阴性菌的新型有效药物，因此必须探索其他治疗方案。本申请拟制备针对CR-Kp的荚膜多糖（CPS）的单克隆抗体。40株CR-KP分离株的分子胶囊分型表明，尽管具有共同的ST258克隆背景，但这些分离株的CPS是异质的，因此必须生成交叉反应的单克隆抗体，以成功覆盖临床分离株的可变性。在目标1中，我们提出了几种策略来产生交叉反应的单克隆抗体，并增加产生IgG的杂交瘤的数量，因为这种同型是首选的同型。在目标2中，我们建议表征单克隆抗体与不同Cr-Kp胶囊类型结合并有效增强宿主的能力

DESCRIPTION (provided by applicant): Carbapenem resistant Klebsiella pneumonia (CR-Kp) isolates are emerging worldwide including in the US. The CDC has reported an increase in prevalence from 1.6% in 2001 to 10.4% in 2011. CR-Kp causes predominantly pneumonia, sepsis and urinary tract infections. Most patients acquire this pathogen in health care associated settings but infections with CR-Kp have also been observed in healthy people from the community. One problem is that many of the CR-Kp isolates retain full virulence and often become resistant even to aminoglycosides. The 2nd line reserve antibiotics such as Tycycline or Polymyxin either have low efficacy or are very toxic especially in patients with compromised renal function. As a result, the mortality of invasive Cr-Kp infections is high and ranges from 50-80%. New effective drug classes against gram-negative bacteria are not in sight hence alternative treatment regimens have to be explored. This application proposes to generate mAbs to the capsular polysaccharide (CPS) of CR-Kp. Molecular capsule typing of 40 CR-KP isolates demonstrates that despite a common ST258 clonal background the CPS in these isolates is heterogeneous and therefore cross-reactive mAbs will have to be generated in order to successfully cover the variability of clinical isolates. In aim 1 we propose several strategies o generate cross-reactive mAbs and to also increase the number of hybridomas that produce IgG as this isotype is the preferred isotype. In aim 2 we propose to characterize the mAbs with respect to their ability to bind to diverse capsule-types of Cr-Kp and effectively enhance the host response to diverse Cr-Kp isolates. The goal is to generate a rank list of best candidates that are then humanized and further developed.