The Detection And Clinical Significance Of Circulating Follicular Helper T And B Cells In Patients With With Newly Diagnosed Primary Biliary Cirrhosis

Objective: To study the expression of the numbers of different subsets ofcirculating Tfh and B cells, and evaluating their potential association with the levelsof clinic measures such as immunoglobulins and autoantibodies in newly diagnosedPBC patients as well as further investigate the probably role of Tfh and B cells in theimmunity response.Methods: The numbers of circulating CD27+, CD38+, CD86+, CD95+B cells,inducible T cell costimulator (ICOS)+, programmed death-1(PD-1)+, IL-21+TFHcells and the levels of serum IL-21were examined in58patients with newlydiagnosed PBC and30matched healthy controls (HC) by flow cytometry analysisand Enzyme-linked immunosorbent assay (ELISA). Then The levels of serumalanine transaminase (ALT), spartate aminotransferase (AST), alkaline phosphatase(ALP), gamma glutamyl transpeptidase (GGT) were detected by the enzymecolorimetric assay according the manufacturers’ instructions (Huachenbio, Shanghai,China). The concentrations of IgG, IgM and IgA were detected by the scatteredturbidimetry on a Siemens special protein analysis instrument (Siemens HealthcareDiagnostics Products, GmbH, Germany). The concentrations of anti-mitochondrialantibodies (AMA) and anti-mitochondrial-M2antibodies (AMA-M2), anti-nuclearantibodies (ANA), anti-cyclic citrullinated peptide antibodies (CCP) were detectedby the enzyme-linked immunosorbent assay (ELISA) according to themanufacturers’ instruction (R&D Systems, Minneapolis, MN, USA).Results:1. The numbers of circulating CD19+CD86+, CD19+CD95+B cells and CD38+plasma cells; CD3+CD4+CXCR5+ICOS+and CD3+CD4+CXCR5+PD-1+Tfh cells; and the levels of serum IL-21in the newly diagnosed PBC patientswere significantly greater, but the numbers of CD27+CD19+B cells weresignificantly less than those in the HC (both for p <0.05).2. The numbers ofCD3+CD4+CXCR5+ICOS+Tfh cells were positively correlated with the numbersof CD19+CD38+plasma cells and CD19+CD86+CD38+B cells （P=0.0005,R=0.4460; P=0.0004, R=0.4488）, but the levels of serum IL-21were negativelywith the numbers of CD27+CD19+B cells (P<0.0001, R=-0.5014) in the newlydiagnosed PBC patients.3. The numbers of CD19+CD38+plasma cells werepositively correlated with the concentrations of serum AMA-M2, AMA, IgM andIgG in the newly diagnosed PBC patients (P=0.0001, R=0.4862; P=0.0038,R=0.3739; P=0.0022, R=0.3938； P=0.0003, R=0.4537).4. The numbers ofCD3+CD4+CXCR5+ICOS+Tfh cells were positively correlated with the levels ofserum anti-mitochondrial antibodies against M2antigen (AMA-M2), AMA andimmunolgubin M (IgM)(P=0.0006, R=0.4265; P=0.0006, R=0.4883;P=0.0007,R=0.4337), while the levels of serum IL-21were correlated positively with the levelsof serum AMA-M2, AMA, IgG and IgM (P=0.004, R=0.3720; P=0.0002,R=0.4675;P=0.0008, R=0.4294; P=0.0036, R=0.3736) in the newly diagnosed PBCpatients.Conclusions:1. An imbalance of different subsets of B cells leads to theupregulation of CD19+CD38+plasma cells in patients with newly diagnosed PBC,which indicates that increased numbers of circulating CD19+CD38+plasma cellsmaybe responsible for producing autoantibodies during the pathogenic process ofPBC.2. Abnormal activation of circulating Tfh cells regulate functional B cellsdifferentiation and humoral responses by the certain functional surface molecules ansecreting IL-21, which leads to the production of autoantibodies and thedevelopment of hyperimmunoglobulinemia during the pathogenesis of PBC.3.Circulating ICOS+Tfh cells and serum IL-21may be a potential target for the intervention of PBC, which provides a new way for clinical practice.