目的：本研究通过血清外泌体蛋白质组学分析,寻找侵袭性白念珠菌感染的标志物。方法：尾静脉注射白念珠菌菌液建立小鼠模型。提取血清外泌体,分离富集血清外泌体,液相色谱-质谱分析外泌体蛋白质组学。构建金黄色葡萄球菌和大肠埃希菌感染模型,比较外泌体差异蛋白在3个感染组的表达差异。结果：共鉴定4 055个不同肽段,对应418个蛋白质。以符合白念珠菌组/正常对照组差异变化<0.5倍至>2.0倍,同时P<0.05为标准,筛查出差异蛋白10个。对与白念珠菌感染密切相关的蛋白质Cathepsin B、Pentraxin 3进行ELISA鉴定,建立受试者工作特征曲线诊断模型,发现外泌体差异蛋白具有很高的灵敏度和特异度。在3个不同的感染组中,发现外泌体差异蛋白大量在白念珠菌感染组中表达,在非白念珠菌感染组中少量表达。结论：Cathepsin B、Pentraxin 3与白念珠菌感染密切相关,可作为白念珠菌感染的分子标志。

Objective To analyze serum exosome using proteomic in mice with Candida albicans infection and to find out marker. Methods Mice model of Candida albicans infection was established by injection of Candida albicans liquid through tail vein. Exosome in serum were extracted and analyzed by liquid chromatography-mass spectrometry/mass spectrometry. Mice models of both Staphylococcus aureus infection and Escherichia coli infection were established to compare the protein expression in exosome among three groups of infection. Results A total of 4 055 peptides and 418 proteins were identified. With the ratio <0.5 or >2.0 times between Candida albicans infection group and normal control group and with P<0.05, 10 of different proteins were screened out. Both Cathepsin B and Pentraxin 3 which were related with Candida albicans infection were identified by ELISA. Receiver operating characteristic curves were used to evaluate proteins and the different proteins in exosome were found to have high sensitivity and specificity. In 3 groups of Candida albicans infection, Staphylococcus aureus infection and Escherichia coli infection, it was found that exosome proteins expressed more in Candida albicans infection group and less in the other two infection group. Conclusions Proteins including Cathepsin B and Pentraxin 3 were related to Candida albicans infection, which could be used as molecular markers of Candida albicans infection.