Department of Comparative Biochemistry and Bioanalytics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University in Krakow, Krakow, Poland.
Department of Analytical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University in Krakow, Krakow, Poland.
Yeast. 2023 Aug;40(8):377-389. doi: 10.1002/yea.3847. Epub 2023 Mar 14.
One of the initial steps necessary for the development of Candida infections is the adherence to the host tissues and cells. Recent transcriptomic studies suggest that, in Candida parapsilosis-a fungal infectious agent that causes systemic candidiasis in immunosuppressed individuals-the adhesion is mediated by pathogen cell-exposed proteins belonging to the agglutinin-like sequence (Als) family. However, to date, the actual interactions of individual members of this family with human cells and extracellular matrix (ECM) have not been characterized in detail. In the current study, we focused attention on two of these C. parapsilosis Als proteins-CPAR2_404800 and CPAR2_404780-that were proteomically identified in the fungal cell wall of yeasts grown in the media suitable for culturing human epithelial and endothelial cells. Both proteins were extracted from the cell wall and purified, and using a microplate binding assay and a fluorescence microscopic analysis were shown to adhere to human cells of A431 (epithelial) and HMEC-1 (endothelial) lines. The human extracellular matrix components that are also plasma proteins-fibronectin and vitronectin-enhanced these interactions, and also could directly bind to CPAR2_404800 and CPAR2_404780 proteins, with a high affinity (K in a range of 10 to 10 M) as determined by surface plasmon resonance measurements. Our findings highlight the role of proteins CPAR2_404800 and CPAR2_404780 in adhesion to host cells and proteins, contributing to the knowledge of the mechanisms of host-pathogen interactions during C. parapsilosis-caused infections.
念珠菌属感染发展的必要初始步骤之一是与宿主组织和细胞黏附。最近的转录组学研究表明，在念珠菌属副假丝酵母（一种真菌性传染病原，会导致免疫抑制个体发生系统性念珠菌病）中，黏附是由病原体细胞暴露的凝集素样序列（Als）家族蛋白介导的。然而，迄今为止，尚未详细描述该家族个别成员与人类细胞和细胞外基质（ECM）的实际相互作用。在本研究中，我们将注意力集中在两种 CP. parapsilosis Als 蛋白上，即 CPAR2_404800 和 CPAR2_404780，它们在适合培养人类上皮细胞和内皮细胞的培养基中生长的酵母真菌细胞壁中通过蛋白质组学方法被鉴定出来。这两种蛋白均从细胞壁中提取并纯化，通过微量板结合试验和荧光显微镜分析表明，它们可黏附于人 A431（上皮）和 HMEC-1（内皮）系细胞。人类细胞外基质成分（也是血浆蛋白）纤连蛋白和 vitronectin 增强了这些相互作用，并且还可以直接与 CPAR2_404800 和 CPAR2_404780 蛋白结合，亲和力很高（根据表面等离子体共振测量，Kd 值在 10 到 10 M 范围内）。我们的研究结果强调了 CPAR2_404800 和 CPAR2_404780 蛋白在与宿主细胞和蛋白黏附中的作用，有助于了解念珠菌属副假丝酵母引起的感染中宿主-病原体相互作用的机制。
