Quorum sensing signal molecule modulation of immunity: role in host responses to P. aeruginosa lung infection

铜绿假单胞菌是一种导致人类严重感染的细菌，特别是那些患有囊性纤维化，或免疫功能低下，遭受严重烧伤或长期导尿管的人。本研究将探讨铜绿假单胞菌如何通过产生称为群体感应信号分子（QSSM）的分子来增加其毒力。我们认为，这种细菌产生的这些QSSMs使它们能够通过影响宿主的免疫系统来影响宿主的反应。我们将研究这种QSSM如何抑制免疫，以及这对感染的严重程度和慢性感染的发展潜力有什么影响。这项研究将首先确定QSSM在哪里发挥作用（也就是说，它能否从感染部位逃出来影响其他宿主部位），这将指导我们如何更多地了解它在感染期间影响宿主的方式。我们将研究QSSM对急性和慢性铜绿假单胞菌肺部感染的直接影响，然后从中确定结果是否会加剧随后的感染。这项工作意义重大，因为对这些毒力因素的认识和理解将有助于设计更好的治疗和预防策略，以预防易感个体的感染和治疗那些遭受慢性感染的人。

Pseudomonas aeruginosa is a bacterium that causes serious infections in humans, particularly those with Cystic Fibrosis, or who are immunocompromised, suffering serious burn injuries or have long term catheters. This study will investigate how P. aeruginosa may be able to increase its virulence by producing molecules known as Quorum Sensing Signal Molecules (QSSM). We believe the production of these QSSMs by this bacterium enables them to affect how the host responds by affecting their immune system. We will be investigating how this QSSM may suppress immunity and what influence this has on both the severity of infection and the potential for development of chronic infection. The study will first of all determine where the QSSM exerts its effects (that is, can it escape from the site of infection to affect other host sites) and this will direct us in how we may learn more about the way it can affect the host during an infection. We will investigate the direct affects of QSSM on acute and chronic types of P. aeruginosa lung infection and then from this, determine if the outcome exacerbates a subsequent infection. The work is significant in that a knowledge and understanding of these virulence factors will assist in the design of better therapeutic and prophylactic strategies for both prevention of infection in susceptible individuals and treatment of those that suffer from chronic infection.