Increased Numbers of Circulating ICOS+ Follicular Helper T and CD38+ Plasma Cells in Patients with Newly Diagnosed Primary Biliary Cirrhosis

Abstract

Background: Aberrant activation of follicular helper T (TFH) and B cells is associated with the development of autoimmune diseases. However, little is known about the potential role of these cells in the development of primary biliary cirrhosis (PBC). Aim: This study aimed at characterizing the numbers of different subsets of circulating Tfh and B cells as well as evaluating their potential association with the levels of immunoglobulins and autoantibodies in newly diagnosed PBC patients. Methods: The numbers of circulating CD27+, CD38+, CD86+ and CD95+ B cells as well as inducible T cell costimulator (ICOS)+ and programmed death-1 (PD-1)+, IL-21+ TFH cells were examined in 58 patients with newly diagnosed PBC and 30 matched healthy controls (HCs). Results: The numbers of circulating CD38+CD19+, CD86+CD19+, and CD95+CD19+ B cells; CD3+CD4+CXCR5+ICOS+ and CD3+CD4+CXCR5+PD-1+ Tfh cells; and the levels of serum IL-21 in the PBC patients were significantly greater, but the numbers of CD27+CD19+ B cells were significantly less than those in the HCs (p < 0.05). The numbers of CD3+CD4+CXCR5+ICOS+ Tfh cells were positively correlated with the numbers of CD38+CD19+ and CD86+CD38+CD19+ B cells and the levels of serum anti-mitochondrial antibodies against M2 antigen (AMA-M2), AMA and immunolgubin M (IgM) in the PBC patients. The levels of serum IL-21 were positively correlated with the levels of serum AMA-M2, AMA, IgG and IgM, but negatively with the numbers of CD27+CD19+ B cells in the PBC patients. Conclusions: Increased numbers of circulating ICOS+ and IL-21+ Tfh and CD38+ plasma cells may be exhibited by patients with recent diagnoses of PBC.