抗合成酶综合征的肠道菌群特点

Characteristics of intestinal flora in anti-synthetase syndrome

目的探究抗合成酶综合征(ASS)患者和健康人群的肠道菌群是否存在差异。方法选择四川大学华西医院2022年2月至10月在风湿免疫科就诊的22例ASS患者以及26例健康对照者作为研究对象。收集患者和健康者粪便样品的细菌总DNA,通过Illumina MiSeq平台对样本16S rRNA基因序列V3-V4高变区进行PCR扩增及测序,并进行组间OTU分析、样品多样性分析、样品组间显著性差异分析及LEfSe分析。利用Spearman相关系数计算菌属与ASS临床特征的相关性。通过随机森林分类结果绘制ROC曲线。结果ASS组与健康对照组肠道菌群组成存在显著差异,α多样性指数(Simpson、chao1)在ASS组明显降低,β多样性分析显示两组间菌群结构存在明显差异。在菌群组成上,ASS组表现为拟杆菌门减少,厚壁菌门增多。LEfSe差异分析发现ASS组链球菌属(Streptococcus)和肠球菌属(Enterococcus)是优势菌属;而健康对照琼脂杆菌属(Agathobacter),瘤胃球菌属(Ruminococcus),拟杆菌属(Bacteroides)等产丁酸菌是优势菌属。Spearman相关系数分析结果显示志贺埃希菌属(Escherichia-Shigella)与ASS患者技工手症状正相关(r>0,P<0.05)。利用7种菌属区分ASS和健康人,AUC=0.85(95%CI:0.75~0.96),具有较好的诊断效能。结论ASS患者和健康人群的肠道菌群存在显著差异,提示在ASS发生发展过程中肠道菌群的改变可能起到了重要作用。

Objective To investigate the differences in the intestinal microbiota between patients with anti-synthetase syndrome(ASS)and healthy controls.Methods Twenty-two ASS patients and 26 healthy controls were enrolled from the Department of Rheumatology and Immunology,West China Hospital from February to October 2022.Total bacterial DNA was extracted from fecal samples of patients and healthy controls.PCR amplification and sequencing of 16S rRNA gene sequences V3-V4 hypervariable regions were performed on the Illumina MiSeq platform.OTU analysis,sample diversity analysis,sample intergroup significant difference analysis,and LEfSe analysis were performed.Spearman correlation coefficient was used to calculate the correlation between genera and clinical characteristics of ASS.ROC curve was drawn by random forest classification results.Results The results showed that there were significant differences in the intestinal microbiota composition between the ASS group and the healthy control group.The alpha diversity index(Simpson,chao1)was significantly decreased in the ASS group,and the beta diversity analysis showed significant differences in the microbial structure between the two groups.In terms of microbial composition,the ASS group showed a decrease in the Proteobacteria and an increase in the Firmicutes.LEfSe analysis showed that Streptococcus and Enterococcus were the dominant genera in the ASS group,while Agathobacter,Ruminococcus,and Bacteroides were the dominant genera in the healthy group.Spearman correlation coefficient analysis showed that Escherichia-Shigella was positively correlated with mechanic’s hands in ASS patients(r>0,P<0.05).Seven genera were used to distinguish ASS and healthy people,with an AUC of 0.85(95%CI:0.75-0.96),which had a good diagnostic effect.Conclusions There are significant differences in the gut microbiota between patients with ASS and healthy individuals.It indicates that changes in the gut microbiota may play an important role in the occurrence and development of ASS.