The Correlation Of Altered Gut Microbiome And Expression Of Tfr/Tfh Cells In Peripheral Blood Of Patients With Rheumatoid Arthritis

Background:Rheumatoid arthritis(RA)is a highly disabling autoimmune disease.The pathogenesis is still unclear and the destruction of immune tolerance is confirmed to be the important link.Follicular helper T cells(Tfh)can promote B cell proliferation and the production of antibody,while follicular regulatory T cells(Tfr)can inhibit the production of high-affinity antibody to maintain immune tolerance.And the balance of the two plays opposite roles in humoral immune regulation to maintain immune tolerance homeostasis.Tfr and Tfh cells are also expressed in peripheral blood,and there are memory phenotype cells(CD45RA-Tfr cells and PD-1+Tfh cells),which can play a role in the early stage of immune response.The imbalanced number and function of Tfr,Tfh and memory phenotype cells can lead to the excessive production of abnormal autoantibodies,which may be the key to the pathogenesis of RA.The gut microbiota plays an immunoregulatory role and regulates the human immune system.The interaction and regulation mechanism of gut microbiota with the balance of Tfr/Tfh is a frontier focus of immunology research.The gut microbiota may be one of the root mechanisms for regulating the balance of Tfr/Tfh.Dysbiosis of gut microbiome can affect the development and function of Tfr and Tfh cells,and destroy immune tolerance,which is an important source of impaired immune tolerance.At present,the research on Tfr,Tfh and memory phenotype cells in peripheral blood of RA at home and abroad is still in the exploratory stage,especially the effect of gut microbiome on Tfr,Tfh and memory phenotype cells is few and not clear.The aim of this study was to clarify the composition of gut microbiome and the expression of Tfr,Tfh and memory phenotype cells in peripheral blood of RA,and to clarify the relationship between the altered gut microbiota and Tfr,Tfh and memory phenotype cells in peripheral blood,in order to reveal the mechanism of the occurrence and development of RA,and to provide targeted and individualized immunoregulatory therapy for RA.Objective:By detecting the expression levels of Tfr,Tfh and memory phenotype cells in peripheral blood of new-onset RA,and analyzing the correlation with the disease activity,autoantibodies to explore the role of Tfr,Tfh and memory phenotype cells in the disease progression of RA.Furthermore,by analyzing the correlation between altered gut microbiome changes and peripheral blood Tfr,Tfh and memory phenotype cells in new-onset RA patients to clarify the relationship between the altered gut microbiota and Tfr,Tfh and memory phenotype cells in peripheral blood of RA.Methods:According to the inclusion and exclusion criteria,32 new-onset RA patients(new-onset RA group)and 17 healthy persons(HC)were enrolled.The demographic data,peripheral blood and stool specimens were collected from the two groups.The expression of Tfr cells,m Tfr cells,Tfh cells and PD-1+Tfh cells in the peripheral blood were detected and compared by flow cytometry.The composition of gut microbiome was detected and compared by 16 S r RNA gene sequencing technology.At the same time,the clinical symptoms and laboratory indicators(including erythrocyte sedimentation rate,C-reactive protein,autospecific antibodies such as anti-CCP antibodies,etc.)of new-onset RA patients were collected,and the DAS28 score of new-onset RA patients was calculated to analyze the correlation.Results:1.Compared with healthy controls,the percentage of Tfr cells in CD4+T cells[1.340(0.360,2.378)vs2.310(1.320,3.320),P=0.032],the percentage of m Tfr cells in CD4+T cells[1.332(0.282,2.224)vs2.097(1.143,3.130),P=0.032],the absolute number of Tfr cells[0.756(0.127,1.812)vs1.422(0.882,1.893),P=0.025],the absolute number of m Tfr cells [7.690(1.700,15.202)vs14.519(8.979,28.602),P=0.008],the absolute number of Tfh cells [240.443(185.774,291.153)vs328.307(240.661,405.103),P=0.032] and the ratio of m Tfr/PD-1+Tfh[0.114(0.037,0.248)vs0.522(0.255,1.502),P<0.001] in peripheral blood of new-onset RA patients were decreased.But the percentage of PD-1+Tfh cells in CD4+T cells [8.955(5.580,13.550)vs2.750(0.923,12.965),P=0.044] of RA was increased.2.In peripheral blood of new-onset RA patients,the percentage of Tfr cells in CD4+T cells was negatively correlated with the count of joint tenderness(r=-0.451,P=0.011),DAS28 score(r=-0.430,P=0.014),and the absolute number of Tfr cells was negatively correlated with ESR(r=-0.400,P=0.023),the count of joint tenderness(r=-0.483,P=0.006),DAS28 score(r=-0.551,P=0.001)and the titer of anti-CCP antibody(r=-0.829,P=0.042),the absolute number Tfh cells was negatively correlated with CRP(r=-0.451,P=0.010).3.Compared with healthy controls,the α diversity of gut microbiome in new-onset RA patients was increased(P<0.05),and the β diversity was different(P<0.05).4.The composition of gut microbiome in new-onset RA patients was different from that in healthy controls.The abundance of Enterobacteriales at the order level(P=0.022)and the abundance of Enterobacteriaceae at the family level(P=0.023)were increased in HC group and had the greatest impact(LDA value>3,P<0.05),the abundance of Ruminococcus＿2(P=0.045)and Ruminococcaceae＿UCG-002(P=0.032)at the genus level were elevated in new-onset RA group and had the greatest impact(LDA value>3,P<0.05).5.The abundance of Ruminococcaceae＿UCG-002 in new-onset RA group was negatively correlated with the count of joint tenderness(r=-0.407,P=0.023)and DAS28score(r=-0.372,P=0.036).6.In new-onset RA group,the abundance of Ruminococcus＿2 was negatively correlated with the percentage of Tfr cells(r=-0.520,P=0.002),the absolute number of Tfr cells(r=-0.643,P<0.001),the absolute number of m Tfr cells(r=-0.651,P<0.001)and the ratio of m Tfr/PD-1+Tfh(r=-0.487,P=0.005)in peripheral blood.Conclusion:There is an imbalance of m Tfr/PD-1+Tfh in new-onset RA patients,and the expression of peripheral blood Tfr cells is related to disease activity and the production of antibody,which may become an evaluation index for the disease progression and a target cell for treatment of RA.The gut microbiome in new-onset RA patients is disordered,and the increase of the Ruminococcus＿2 is related with the reduced Tfr and m Tfr cells and the imbalance of m Tfr/PD-1+Tfh.