艾滋病患者肠道真菌菌群及真菌分泌蛋白表达情况研究

Study on the Microecological Changes and Secreted Protein Expression of Intestinal Fungi in AIDS Patients

目的对比AIDS期患者与健康者肠道真菌微生态、真菌分泌蛋白表达水平的差异。方法采集两组人群粪便标本,分别用ITS2高通量测序技术分析样本真菌谱;通过RT-qPCR技术检测两组人群肠道真菌分泌蛋白的基因表达。结果在门水平,两组人群中相对丰度最高的菌门均为子囊菌门,相对丰度排名第二的菌门均为担子菌门。在纲、目水平,两组人群相对丰度较高的物种相似,但也存在差异。在肠道真菌群落多样性(Alpha多样性)分析中,两组之间差异无统计学意义。在肠道真菌群落结构构成(Beta多样性)分析中,两组之间差异有统计学意义(P<0.05)。AIDS期患者组肠道白念珠菌相对丰度较健康者组上升,但是两组人群之间白念珠菌丰度差异无统计学意义(Z=-1.843,P=0.065);白念珠菌致病因子ALS3在AIDS期患者组表达情况较健康者组显著上升(Z=2.467,P=0.014)。相关性分析发现Flaviporus属与CD4+T细胞数(r=0.555,P=0.001)和CD4/CD8(r=0.507,P=0.002)呈显著的正相关关系,Ophiosphaerella属与CD4+T细胞数(r=0.450,P=0.007)呈显著的正相关关系。结论与健康人群对比,AIDS期患者的肠道真菌微生态及部分分泌蛋白水平发生了明显变化,恢复正常的肠道微生态有利于维持AIDS期患者肠道屏障的完整性。

Objective To compare the differences in the microecology of intestinal fungi and their secreted proteins between AIDS patients and healthy people.Methods We collected stool specimens of healthy controls and AIDS patients.ITS1 high-throughput sequencing and RT-qPCR detection were performed subsequently to analyze fungal composition as well as fungal secreted protein genes of the two groups.Results At the phylum level,the highest relative abundance in both groups was Ascomycetes,and the second highest relative abundance was Basidiomycota.At the level of class and order,the species with high relative abundance were similar in both populations.There was not statistical significant difference in the diversity of intestinal fungal species(Alpha diversity)between the two populations.The relative abundance of Candida albicans increased in the group of AIDS patients compared with the healthy group,but the difference in the abundance was no tstatistically significant(Z=-1.843,P=0.065).The expression of pathogenic factor ALS3 of Candida albicans in AIDS patients was higher than that inthe healthy group(Z=2.467,P=0.014).By the correlation analysis,we found that Flaviporus was significantly correlated with CD4+T cell count(r=0.555,P=0.001)and CD4/CD8(r=0.507,P=0.002).Ophiosphaerella is significantly correlated with the number of CD4+T cells(r=0.450,P=0.007).Conclusion Compared with the healthy population,the levels of intestinal fungal microecology and fungal secreted proteins change significantly in AIDS patients,and the restoration of normal intestinal microecologyis is supposed to contribute in maintaining the integrity of the intestinal barrier of AIDS patients.