Usefulness of chemokine C-C receptor 7-/programmed cell death-1+ follicular helper T cell subset frequencies in the diagnosis of autoimmune hepatitis

Aim A significant concern for autoimmune hepatitis (AIH) patients is diagnostic specificity. Delayed treatment due to delayed diagnosis leads to poor survival. We recently reported that chemokine C-C receptor 7 (CCR7)(-)/programmed cell death-1 (PD-1)(+) follicular helper T (Tfh) cells could be involved in AIH pathogenesis. We hypothesized that Tfh cell frequencies might contribute to AIH diagnosis. Methods Peripheral blood was collected from 12 patients with AIH from April 2013 to March 2016, as well as 24 patients with hepatitis B virus (HBV) infection and 44 healthy controls (HC). Mononuclear cells were separated using a Ficoll gradient, and surface markers were investigated using flow cytometry. Results The frequency of CCR7(-)PD-1(+) Tfh cells was significantly higher in AIH patients (39.1 +/- 8.6) compared to that in HC (25.1 +/- 7.9%, P < 0.01) and HBV patients (22.7 +/- 7.8, P < 0.01). The area under the receiver operating characteristic curve for the frequency of the CCR7(-)PD-1(+) Tfh cell subset for AIH and HC and AIH and HBV was 0.905 and 0.927, respectively. The frequency of the CCR7(-)PD-1(+) Tfh cell subset was not correlated with International Autoimmune Hepatitis Group (IAIHG) scoring, Simplified AIH scoring, or Japanese diagnostic guidelines (R = 0.10, 0.947; R = 0.0008, 0.180; and R = 0.348, 0.558, respectively). Therefore, these frequencies could diagnose AIH patients who were not diagnosed with the IAIHG or simplified AIH scores. Conclusions The frequency of the peripheral CCR7(-)PD-1(+) Tfh cell subset could be useful for diagnosing AIH even in patients who were not diagnosed with IAIHG or simplified AIH scores.