Candida-endothelial interactions under conditions of flow

描述（由申请人提供）：问题：系统性念珠菌病是一种严重的感染，死亡率高。循环真菌细胞进入组织并造成广泛的器官损伤导致死亡。该过程的第一步是粘附到血管的内皮衬里，然后穿过内皮屏障进入组织。然而，我们对这些步骤中的任何一个所涉及的机制知之甚少，并且关于白色念珠菌的酵母和菌丝形式在粘附和迁移过程中所起的作用存在相互矛盾的证据。背景资料：迄今为止，大多数探索念珠菌粘附于内皮的体外研究都是在静态条件下进行的，尽管很明显，粘附过程在体内血管中发生的流动条件下非常不同。研究形态发生变化在这些过程中的重要性一直是困难的，因为大多数C。在这些研究中使用的白色念珠菌被锁定成一种或其他形态形式，并具有降低的毒力，而野生型C.白色念珠菌是不可预测和难以控制的。 在初步研究中，我们已经开发了一种工程化的C。白色念珠菌，SSY 50-B，其中我们可以调节从酵母到菌丝形式的形态发生转化，同时保持生物体的毒力。另外，我们已经开发了检测方法，使我们能够研究细胞，特别是白细胞和肿瘤细胞，在类似于血管中的流动条件下粘附到内皮表面，并跟踪其随后的跨内皮迁移。我们的目标是把这些技术结合在一起，这样我们就可以研究许多关于C语言如何实现的未解答的问题。在系统性念珠菌病中，白色念珠菌从循环进入组织。更具体地说，我们的目标是： 具体目标1：建立一种体外模型，用于研究和比较流动条件下白色念珠菌酵母菌和菌丝体与血管内皮细胞的粘附特性。 具体目标2：建立一种体外模型来研究C.白念珠菌的流动条件下，以探讨在轮回过程中的酵母形式，菌丝形式和形态发生转换的作用。 公益：系统性真菌病是一种严重的危及生命的疾病，其中循环真菌细胞粘附并迁移穿过血管的内皮衬里进入组织，在那里它们引起广泛的器官损伤。通过了解念珠菌-内皮细胞粘附和迁移的机制，我们可能能够抑制念珠菌迁移到组织中，防止由此产生的组织损伤，并增加循环生物体对抗真菌剂和网状内皮系统的暴露，从而将其破坏。

DESCRIPTION (provided by applicant): Problem: Systemic candidiasis is a serious infection with high mortality. Death results from circulating fungal cells entering the tissues and causing extensive organ damage. The first step in this process is adhesion to the endothelial lining of blood vessels followed by transmigration across the endothelial barrier into the tissues. However, we know little about the mechanisms involved in either of these steps and there is conflicting evidence about the role played by yeast and hyphal forms of Candida albicans in both the adhesion and transmigration process. Background: To date, most in vitro studies exploring candidal adhesion to endothelium have been performed under static conditions although it is clear that adhesion processes are very different under the conditions of flow that occur in blood vessels in vivo. Studying the importance of morphogenetic change in these processes has been difficult, because most mutant strains of C. albicans used in these studies are locked into one or other morphological form and have reduced virulence, while morphogenetic conversion of wild type C. albicans is unpredictable and difficult to control. In preliminary studies, we have developed an engineered stain of C. albicans, SSY50-B, in which we can regulate morphogenetic conversion from yeast to hyphal form whilst maintaining the organism's virulence. Separately we have developed assays that allow us to study the adhesion of cells, particularly leukocytes and tumor cells, to endothelial surfaces under conditions of flow similar to those in blood vessels and to follow their subsequent trans-endothelial migration. Our objective is to bring these technologies together so that we can investigate many of the unanswered questions about how C. albicans moves from the circulation into the tissues in systemic candidiasis. More specifically our aims are: Specific aim 1: To develop an in vitro model that will allow us to study and compare the adhesion characteristics of yeast and hyphal forms of Candida albicans to vascular endothelium under conditions of flow. Specific aim 2: To develop an in vitro model to study the trans-endothelial cell migration of C. albicans under conditions of flow, in order to investigate the role of yeast forms, hyphal forms and morphogenetic conversion in the transmigration process. Public benefit: Systemic Candidiasis is a serious life threatening condition in which circulating fungal cells adhere to and migrate across the endothelial lining of blood vessels to enter the tissues where they cause extensive organ damage. By understand the mechanisms involved in Candida-endothelial adhesion and transmigration, we may be able to inhibit Candida migration into the tissues, prevent the resulting tissue damage and increase the exposure of circulating organisms to anti-fungal agents and the reticuloendothelial system so that they can be destroyed.