Compartmentalization and its implication for peripheral immunologically-competent cells to the liver in patients with HBV-related acute-on-chronic liver failure

Aims: This study attempts to characterize the feature of immunologically competent cells (ICCs) and evaluate its clinical implication in patients with acute-on-chronic liver failure (ACLF) in relation to chronic hepatitis B virus (HBV) infection. Methods: Circulating ICCs were examined in ACLF patients (n = 75), as well as in patients with hepatitis B (CHB, n = 31), CHB-related liver cirrhosis (LC, n = 36), and normal controls (NC, n = 30). Intrahepatic ICCs in some patients were further analyzed via immunohistochemical and flow cytometric assays. Results: Total lymphocytes, CD4+ T cells, CD8+ T cells, and NK cells in circulation were numerically lower in the ACLF and LC groups compared to the CHB and NC groups. Importantly, the number of these cells was significantly lower in non-surviving ACLF patients compared with surviving ACLF patients. In comparison to NC, ACLF patients displayed a significantly higher ratio of liver-infiltrating CD4+ T-cell frequency than its circulating counterpart, suggesting that the possiblility of the ICCs compartmentalization from the peripheral blood into the liver in ACLF. Immunohistochemical analysis showed that intrahepatic CD4+ cells, CD8+ cells, and CD56+ cells were significantly higher in the ACLF group compared with the other three groups, suggesting a stronger cellular immune response-mediated inflammation in ACLF group than other patient groups. Conclusions: The abnormal prevalence of circulating and intrahepatic ICCs possibly acts as an important factor that may drive the progression of HBV-related ACLF.