Ramage Gordon, Wickes Brian L, López-Ribot José L
Department of Biology and South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, Texas 78249, USA.
Rev Iberoam Micol. 2008 Mar;25(1):37-40. doi: 10.1016/s1130-1406(08)70009-3.
A variety of manifestations of Candida albicans infections are associated with the formation of biofilms on the surface of biomaterials. In order to maintain their niche these adherent populations need to withstand the continuous bathing action of physiological fluids (saliva, blood), which also provide water and nutrients to the fungal cells. Thus, it was the aim of this study to examine and further characterize the development of C. albicans biofilms under shear forces and a flow of replenishing nutrients, emulating the conditions that fungal cells would normally encounter within the host. An improved modified Robbins device (MRD) was designed to hold six poly methyl methacrylate (PMMA) plugs of 25 mm in diameter. A "seed and feed" model of biofilm formation was then implemented for which the apparatus was initially seeded with a C. albicans cell suspension to allow initial adhesion of fungal cells to the biomaterial. Following this initial step, sterile medium was then pumped through the MRD at a constant flow rate. Scanning electron microscopy (SEM) and confocal scanning laser microscopy (CSLM) demonstrated a high degree of heterogeneity associated with the structure of biofilms formed under flowing conditions using the MRD. In addition, these biofilms displayed a complex three dimensional architecture and increased production of exopolymeric material.
白色念珠菌感染的多种表现形式与生物材料表面生物膜的形成有关。为了维持其生态位，这些附着的菌群需要承受生理流体（唾液、血液）的持续冲洗作用，而生理流体也为真菌细胞提供水和营养物质。因此，本研究的目的是在剪切力和营养物质补充流动的条件下，模拟真菌细胞在宿主体内通常遇到的情况，研究并进一步表征白色念珠菌生物膜的形成。设计了一种改进的改良罗宾斯装置（MRD），用于容纳六个直径为25毫米的聚甲基丙烯酸甲酯（PMMA）塞子。然后实施了一种“接种与补料”生物膜形成模型，该装置首先接种白色念珠菌细胞悬液，以使真菌细胞初始粘附于生物材料。在这一初始步骤之后，无菌培养基以恒定流速泵入MRD。扫描电子显微镜（SEM）和共聚焦扫描激光显微镜（CSLM）显示，使用MRD在流动条件下形成的生物膜结构具有高度的异质性。此外，这些生物膜呈现出复杂的三维结构，并增加了胞外聚合物的产生。
