The characteristics of the immune cell profiles in peripheral blood in cholangiocarcinoma patients

Background Immune related cells are known to be closely related to the therapeutic effects and prognoses of cancer patients. In this study, we analyzed immune cell profiles (ICP) of cholangiocarcinoma patients (CCA). Methods To measure the frequency of immune cells, peripheral blood mononuclear cells of 41 CCA and 10 healthy volunteers (HV) were analyzed by FACS. Results There were significant differences between CCA and HV in ICP, and these differences were a consequence of tumor-bearing status, because many items in ICP before surgery were restored to levels in HV after surgery. Therefore, these changes were specifically attributable to cholangiocarcinoma, and we examined if they can function as biomarkers for therapeutic effects and prognoses. A shorter overall survival was associated with a lower frequency of helper T cells (HT) ( p = 0.001), a higher frequency of effector regulatory T cells (eTregs) ( p = 0.008), and a lower frequency of CD80 + eTregs ( p = 0.024) in the best supportive care group, with a lower frequency of CD25 + naïve Tregs (nTregs) ( p = 0.005) in the chemotherapy group, and with a lower frequency of OX40 + HT ( p = 0.022), CD25 + CD8 + T cells ( p = 0.017), and OX40 + CD8 + T cells ( p = 0.032) in the surgery group. The recurrence factors were a higher frequency of CD4 + T cells ( p = 0.009), CCR6 + nTregs ( p = 0.014), and CXCR3 + nTregs ( p = 0.012), and a lower frequency of PD-1 + HT ( p = 0.006), OX40 + HT ( p = 0.004), CD8 + T cells ( p = 0.001), and CTLA-4 + CD8 + T cells ( p = 0.036). Conclusions The ICP in CCA are specifically attributable to cholangiocarcinoma, and may be biomarkers for therapeutic effects and prognoses. Graphical abstract