Study on the relationship between intestinal flora analysis and CD4 +T lymphocyte subsets in patients with systemic lupus erythematosus / 中华风湿病学杂志

ABSTRACT

Objective:To explore the characteristics of intestinal microbiota in patients with systemic lupus erythematosus (SLE), and further explore the relationship between microbiota and CD4 +T lymphocyte subsets and disease activity. Methods:Fecal samples were collected from 96 patients with SLE, and 96 sex- and age-matched healthy controls (HCs). The gut microbiota were investigated via 16s rRNA sequencing. Flow cytometry was used to detect peripheral CD4 +T lymphocyte subsets of Th1, Th2, Th17 and Treg cells. Indicators of disease activity such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), complement C3 and C4, Systemic lupus erythematosus disease activity index(SLEDAI) for each patient were recorded. Differential abundance analysis was carried out using the edgeR algorithm. The Wilcoxon rank-sum test was used to compare alpha diversity indices, bacterial abundances, and the F/B ratio between groups. R (version 4.0.1) was used for comparative statistics, and Pearson′s correlation analysis was used to assess the correlations between the relative abundances of bacterial genera and serum levels of ESR, CRP, C3 and C4 in the samples. Results:The alpha estimators of richness (ACE and Chao 1) were significantly reduced in SLE feces samples compared with those of HCs ( P<0.01). Bacterial diversity estimators, including the Shannon ( P<0.01) and Simpson′s ( P<0.01) indices, were also significantly lower in SLE. Significant differences in gut microbiota composition between SLE and HCs were found using the edgeR algorithm. Compared with HC, 24 species of bacteria were significantly different in SLE patients at the genus level ( P<0.05). Moreover, there was a significant positive correlation between CRP and Coprococcus ( r=0.30, P=0.014), C4 and Corynebacterium ( r=0.31, P=0.013) and Faecalibacterium( r=0.25, P=0.048), Hemoglobin and Morganella( r=0.41, P=0.001), as well as SLIDA and Corynebacterium( r=0.25, P=0.047). In terms of lymphocyte subsets, there was significant positive correlation between B cells, Treg cells and Eubacterium eligens group, as well as CD8 +T, CD4 +T, NK cells and Corynebacterium. In additional, Th1 was positively correlated with Shigella Escherichia coli ( r=0.52, P=0.008), and Th2 was positively correlated with Dielma ( r=0.51, P<0.001). Conclusion:The abundance and diversity of intestinal flora in SLE patients were significantly reduced, and the differentially expressed bacteria were closely related to the CD4 +T lymphocyte subsets and disease activity indicators of patients.