Background: The function of CD69 expressed on T cells in chronic hepatitis B (CHB) remains unclear. We aimed to elucidate the roles of CD69 on T cells in the disease process and in antiviral therapy for CHB. Methods: We enrolled 335 treatment-naive patients with CHB and 93 patients with CHB on antiviral therapy. CD69, antiviral cytokine production by T cells, T-helper (Th) cells, and inhibitory molecules of T cells were measured using flow cytometry, and clinical-virological characteristics were examined dynamically during antiviral therapy. Results: CD69 expression on CD3+, CD4+, and CD8+ T cells was the lowest in the immune-active phase and was negatively correlated with liver transaminase activity, fibrosis features, inflammatory cytokine production by T cells, and Th-cell frequencies but positively with inhibitory molecules on T cells. CD69 expression on CD3+, CD4+, and CD8+ T cells decreased after 48 weeks of antiviral therapy, and patients with hepatitis B e antigen (HBeAg) seroconversion in week 48 showed lower CD69 expression on T cells at baseline and week 48. The area under the ROC curve of CD69 expression on T cells at baseline for predicting HBeAg seroconversion in week 48 was 0.870, the sensitivity was 0.909, and the specificity was 0.714 (P = 0.002). Conclusions CD69 negatively regulates T-cell immunity during CHB, and its expression decreases with antiviral therapy. CD69 expression predicts HBeAg seroconversion in week 48. CD69 may play an important negative role in regulating T cells and affect the efficacy of antiviral therapy.

Influenza is an acute viral respiratory infection that has caused high morbidity and mortality worldwide. Influenza A virus (IAV) has been found to activate multiple programmed cell death pathways, including ferroptosis. Ferroptosis is a novel form of programmed cell death in which the accumulation of intracellular iron promotes lipid peroxidation, leading to cell death. However, little is known about how influenza viruses induce ferroptosis in the host cells. In this study, based on network pharmacology, we predicted the mechanism of action of Maxing Shigan decoction (MXSGD) in IAV-induced ferroptosis, and found that this process was related to biological processes, cellular components, molecular function and multiple signaling pathways, where the hypoxia inducible factor-1(HIF-1) signaling pathway plays a significant role. Subsequently, we constructed the mouse lung epithelial (MLE-12) cell model by IAV-infected in vitro cell experiments, and revealed that IAV infection induced cellular ferroptosis that was characterized by mitochondrial damage, increased reactive oxygen species (ROS) release, increased total iron and iron ion contents, decreased expression of ferroptosis marker gene recombinant glutathione peroxidase 4 (GPX4), increased expression of acyl-CoA synthetase long chain family member 4 (ACSL4), and enhanced activation of hypoxia inducible factor-1α (HIF-1α), induced nitric oxide synthase (iNOS) and vascular endothelial growth factor (VEGF) in the HIF-1 signaling pathway. Treatment with MXSGD effectively reduced intracellular viral load, while reducing ROS, total iron and ferrous ion contents, repairing mitochondrial results and inhibiting the expression of cellular ferroptosis and the HIF-1 signaling pathway. Finally, based on animal experiments, it was found that MXSGD effectively alleviated pulmonary congestion, edema and inflammation in IAV-infected mice, and inhibited the expression of ferroptosis-related protein and the HIF-1 signaling pathway in lung tissues.
Animals ; Mice ; Ferroptosis ; Network Pharmacology ; Reactive Oxygen Species ; Vascular Endothelial Growth Factor A ; Influenza A virus ; Iron ; Hypoxia