Neutralizing the GBS hemolytic lipid toxin

项目总结 细菌感染引起的人类发病率和死亡率仍然是重大的公共卫生问题。 B组链球菌(GBS)或无乳链球菌在妊娠期引起侵袭性感染 导致早产、死产或新生儿感染。此外，GBS还会在 正常、老年、糖尿病和免疫功能受损的成年人。我们的研究表明，溶血素，即 GBS感染的一个关键毒力因素是一种有色的鸟氨酸鼠李糖脂，也被称为格拉达烯。 这种溶血性脂类毒素对许多宿主细胞具有细胞毒性，导致对新生儿和 成年人类。这项建议的目标是确定其他无毒的类似物，以防止毒素 利用小鼠感染模型，阐明宿主免疫机制在GBS感染过程中的作用 对于模拟介导的对这种GBS毒素的免疫很重要，以确定膜小泡是如何 加重GBS的发病机制，如果抗体可以减弱其影响。总体而言，这些研究的结果 AIMS对于预防人类感染GBS将是重要和相关的，并将与其他 由编码有毒脂类的病原体引起的疾病。

PROJECT SUMMARY Human morbidity and mortality due to bacterial infections continue to remain significant public health concern. Group B Streptococcus (GBS) or Streptococcus agalactiae cause invasive infections during pregnancy leading to preterm births, stillbirths or infections in newborns. Furthermore, GBS also cause infections in the normal, elderly, diabetic and immuno-compromised adults. Our work has shown that the hemolysin, which is a key virulence factor for GBS infections is a pigmented ornithine rhamnolipid also known as granadaene. This hemolytic lipid toxin is cytotoxic to a number of host cells leading to adverse outcomes to newborns and adult humans. The objectives of this proposal are to identify additional nontoxic analogs that can prevent toxin function during GBS infections using murine models of infection, to elucidate host immune mechanisms important for analog mediated immunity against this GBS toxin, to determine how membrane vesicles exacerbate GBS pathogenesis and if antibodies can attenuate their effects. Collectively, the results from these aims will be important and relevant for prevention of GBS infections in humans and will be relevant to other diseases caused by pathogens encoding toxic lipids.