Background: The current study explored the characteristics of γδ T cells in the blood of HBV-associated acute-on-chronic liver failure (HBV-ACLF) patients and examined the relationship between γδ T cells and the clinical parameters.
Methods: Blood samples were obtained from 26 patients with HBV-ACLF, 40 patients with chronic hepatitis B virus (HBV) infection (CHBV), and 25 healthy controls (HC). The frequencies of γδ T cells, subtype Vδ1T or Vδ2T, and CD45RO(+)γδ T cells were determined using flow cytometry. Intracellular cytokine staining analysis was used to evaluate the proportion of the IFN-γ-, TNF-α-, or IL-17-producing γδ T cells, and CD107a- or granzyme B-positive γδ T cells.
Results: We found that the proportion of γδ T cells in blood samples from HBV-ACLF patients was much lower than in samples from CHBV patients or healthy controls. After stimulation with PMA and ionomycin, γδ T cells from HBV-ACLF patients produced the greatest amount of TNF-α or IL-17 among the three groups. Granzyme B- or CD107a-positive γδ T cells were significantly more frequent than in CHBV or control samples. There was a negative correlation between the percent of TNF-α(+)γδ T cells and ALT or AST levels, and between the percent of CD107a(+)γδ T cells and TBiL or DBiL levels.
Conclusions: These results suggest that γδ T cells might participate in liver injury in HBV-ACLF patients by producing increased amounts of inflammatory cytokines and/or cytotoxicity ability. These findings provide novel information regarding the pathogenesis of HBV-ACLF.