Characteristics of T cell immune responses in adults inoculated with 2 doses of SARS-CoV-2 inactivated vaccine for 12 months / 解放军医学杂志

Objective To evaluate the characteristics of different antigen-specific T cell immune responses to severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)after inoculation with 2 doses of SARS-CoV-2 inactivated vaccine for 12 months.Methods Fifteen healthy adults were enrolled in this study and blood samples collected at 12 months after receiving two doses of SARS-CoV-2 inactivated vaccine.The level and phenotypic characteristics of SARS-CoV-2 antigen-specific T lymphocytes were detected by activation-induced markers(AIM)based on polychromatic flow cytometry.Results After 12 months of inoculation with 2 doses of SARS-CoV-2 inactivated vaccine,more than 90%of adults had detectable Spike and Non-spike antigen-specific CD4+ T cells immune responses(Spike:14/15,P=0.0001;Non-spike:15/15,P<0.0001).80%of adults had detectable Spike and Non-spike antigen-specific CD8+ T cells immune responses(Spike:12/15,P=0.0463;Non-spike:12/15,P=0.0806).Antigen-specific CD4+ T cells induced by SARS-CoV-2 inactivated vaccination after 12 months were composed of predominantly central memory(CM)and effector memory 1(EM1)cells.On the other hand,in terms of helper subsets,antigen-specific CD4+ T cells mainly showed T helper 1/17(Th1/17)and T helper 2(Th2)phenotypes.Conclusions SARS-CoV-2 inactivated vaccination generates durable and extensive antigen-specific CD4+ T cell memory responses,which may be the key factor for the low proportion of severe coronavirus disease 2019(COVID-19)infection in China.

Exploration of the mechanisms of Ge Gen Decoction against influenza A virus infection / 中国天然药物

Ge Gen Decoction (GGD), a Traditional Chinese Medicine prescription, is mainly used to treat infectious respiratory diseases and can relieve the symptoms of influenza A virus (IAV) infection. However, the underlying mechanism of GGD against IAV infection remains unclear. In this study, we found that GGD had moderate anti-IAV activity in vitro. GGD was more effective when given before the viral infection and targeted the viral attachment and replication stages rather than the internalization stage. In vivo, GGD treatment reduced thevirus titers of lung tissue significantly and improved the survival rate, lung index, and pulmonary histopathological changes in H1N1-infected mice. We observed the changes in several key immuno-related indexes in GGD administrated H1N1-infected mice with anti-IAV drug oseltamivir phosphate as the control. GGD treatment decreased the expression of TNF-α and improved Th1/Th2 immune balance to reduce the excessive immune response in H1N1-infected mice. Besides, the expression of the toll-like receptor 7 signaling pathway in H1N1-infected mice decreased after GGD treatment. Our results showed that GGD has anti-IAV activity and can modulate the immune system to relieve lung inflammation.

Inhibitory effect of Glehniae Radix petroleum ether part on TGF-β1-induced epithelial mesenchymal transition in A549 cells / 中国中药杂志

To study the inhibitory effect of Glehniae Radix petroleum ether part on TGF-β1-induced epithelial mesenchymal transition in non-small cell lung cancer A549 and its possible mechanism. With type Ⅱ epithelial cells of lung cancer A549 as the research object, the experiment was performed in 5 μg•L⁻¹ TGF-β1-induced epithelial mesenchymal transition model,and blank control group, model group and Glehniae Radix petroleum ether group were set up. MTT assay was carried out to detect the effect of petroleum ether extract of Glehniae Radix on the survival of A549 cells. A549 cells induced by TGF-β1(5 μg•L⁻¹) was intervened by different polar parts of Glehniae Radix, Real-time quantitative polymerase chain reaction(RT-qPCR) was used to analyze mRNA expressions of the epithelial mesenchymal transition markers, such as ColⅠ,E-cadherin,Vimentin and α-SMA. Enzyme linked immunosorbent assay(ELISA) was used to detect hydroxyproline(HYP) level. The migration and invasion abilities of cells were detected through wound scratch assay. According to the experimental results, the petroleum ether extract of Glehniae Radix could inhibit the growth of A549 cells in a concentration-dependent manner. Compared with model group, Glehniae Radix petroleum ether part group could effectively inhibit mRNA expressions of ColⅠ,Vimentin and α-SMA, but improve expression of E-cadherin.Glehniae Radix petroleum ether part could reduce the content of hydroxyproline in cells and inhibit the migration of A549 cells.Therefore, the petroleum ether extract of Glehniae Radix can effectively inhibit the occurrence of epithelial mesenchymal transition induced by TGF-β1 induced alveolar epithelial cells, and Glehniae Radix petroleum ether part may be a potential drug for idiopathic pulmonary fibrosis. The mechanism may be achieved through the regulation of ColⅠ, Vimentin, α-SMA and E-cadherin.