It remains challenging to develop animal models of lung infection and severe pneumonia by severe acute respiratory syndrome coronavirus(SARS-CoV) and Middle East respiratory syndrome cornavirus(MERS-Co V) without high...It remains challenging to develop animal models of lung infection and severe pneumonia by severe acute respiratory syndrome coronavirus(SARS-CoV) and Middle East respiratory syndrome cornavirus(MERS-Co V) without high level of containment. This inevitably hinders understanding of virushost interaction and development of appropriate countermeasures. Here we report that intranasal inoculation of sublethal doses of murine coronavirus mouse hepatitis virus A-59(MHV-A59), a hepatic and neuronal tropic coronavirus, can induce acute pneumonia and severe lung injuries in C57BL/6 mice. Inflammatory leukocyte infiltrations, hemorrhages and fibrosis of alveolar walls can be observed 2-11 days after MHV-A59 infection. This pathological manifestation is associated with dramatical elevation of tissue IP-10 and IFN-γ and moderate increase of TNF-α and IL-1β, but inability of anti-viral type I interferon response. These results suggest that intranasal infection of MHV-A59 would serve as a surrogate mouse model of acute respiratory distress syndrome by SARS-CoV and MERS-CoV infections.展开更多
To study the contribution of T cell subsets in the pathogenesis of Murine hepatitis virus Type 3(MHV-3) induced chronic viral hepatitis in C3H/Hej mice,ninety C3H/Hej mice were chosen to individually receive 10 plaque...To study the contribution of T cell subsets in the pathogenesis of Murine hepatitis virus Type 3(MHV-3) induced chronic viral hepatitis in C3H/Hej mice,ninety C3H/Hej mice were chosen to individually receive 10 plaque forming units(PFU)of MHV-3 intraperitoneally.The changes of virus titer and pathology in liver tissue were examined by standard plaque assay and by the hematoxylin/eosin(HE) staining method from 2 days post MHV-3 infection.The ratios of T cell subsets including CD3+CD4+CD8-,CD3+CD4-CD8+,CD3+CD4-CD8-,CD3+CD4+CD25+,CD3+CD4+CD25-and CD3+ CD4-CD25+ T lymphocyte of total T lymphocytes in blood,spleen and liver were examined at 0,2,4,6,8,10,12,15,20,25,30,40 days post MHV-3 infection by flow cytosorting.We observed that the virus titer raised and showed persistent virus duplications and inflammatory changes in the livers of C3H/Hej mice from 2 days post MHV-3 infection.The double negative T cell(DN Treg cell) and CD4+CD25+ T cell ratios increased significantly from 2 days post MHV-3 infection in C3H/Hej mice,and CD3+CD4+CD8-,CD3+CD4-CD8+,CD3+CD4+CD25-and CD3+CD4-CD25+ T cell ratios decreased accordingly.In conclusion,the changes of virus titer and pathology in the livers of C3H/Hej mice post MHV-3 suggest their contribution to viral persistence.Further characterizations of DN Treg cells are that infection indicates that MHV-3 could induce the chronic inflammation in livers of C3H/Hej mice.The increase of the DN Treg cell and CD4+CD25+ T cell ratios in C3H/Hej mice post MHV-3 infection suggests that DN Treg cells and CD4+CD25+ T cells may both have important suppressive immunomodulation functions in the development of chronic viral hepatitis and have important roles in the virus persistent infection.Further characterizations of DNT cell and CD4+CD25+ T cell are under investigation.展开更多
In the maximally-helicity-violating(MHV)configuration,tree-level single-trace Einstein-Yang-Mills(EYM)amplitudes with one or two gravitons have been shown to satisfy a formula in which each graviton splits into a pair...In the maximally-helicity-violating(MHV)configuration,tree-level single-trace Einstein-Yang-Mills(EYM)amplitudes with one or two gravitons have been shown to satisfy a formula in which each graviton splits into a pair of collinear gluons.In this study,we extend this formula to more general cases.We present a general formula that expresses tree-level single-trace MHV amplitudes in terms of pure gluon amplitudes.In this formula,each graviton turns into a pair of collinear gluons.展开更多
基金supported in part by grants from the Natural Science Foundation of China (30430640,31030031)the National Basic Research Program of MOST (2004BA519A61,2003CB514116,2006CB504300)Natural Science Foundation of China (31400765)
文摘It remains challenging to develop animal models of lung infection and severe pneumonia by severe acute respiratory syndrome coronavirus(SARS-CoV) and Middle East respiratory syndrome cornavirus(MERS-Co V) without high level of containment. This inevitably hinders understanding of virushost interaction and development of appropriate countermeasures. Here we report that intranasal inoculation of sublethal doses of murine coronavirus mouse hepatitis virus A-59(MHV-A59), a hepatic and neuronal tropic coronavirus, can induce acute pneumonia and severe lung injuries in C57BL/6 mice. Inflammatory leukocyte infiltrations, hemorrhages and fibrosis of alveolar walls can be observed 2-11 days after MHV-A59 infection. This pathological manifestation is associated with dramatical elevation of tissue IP-10 and IFN-γ and moderate increase of TNF-α and IL-1β, but inability of anti-viral type I interferon response. These results suggest that intranasal infection of MHV-A59 would serve as a surrogate mouse model of acute respiratory distress syndrome by SARS-CoV and MERS-CoV infections.
基金National Nature Science Foundation (30571643, 30672380)Major State Basic Research Development Program of China (2005CB522901,2007CB512904)
文摘To study the contribution of T cell subsets in the pathogenesis of Murine hepatitis virus Type 3(MHV-3) induced chronic viral hepatitis in C3H/Hej mice,ninety C3H/Hej mice were chosen to individually receive 10 plaque forming units(PFU)of MHV-3 intraperitoneally.The changes of virus titer and pathology in liver tissue were examined by standard plaque assay and by the hematoxylin/eosin(HE) staining method from 2 days post MHV-3 infection.The ratios of T cell subsets including CD3+CD4+CD8-,CD3+CD4-CD8+,CD3+CD4-CD8-,CD3+CD4+CD25+,CD3+CD4+CD25-and CD3+ CD4-CD25+ T lymphocyte of total T lymphocytes in blood,spleen and liver were examined at 0,2,4,6,8,10,12,15,20,25,30,40 days post MHV-3 infection by flow cytosorting.We observed that the virus titer raised and showed persistent virus duplications and inflammatory changes in the livers of C3H/Hej mice from 2 days post MHV-3 infection.The double negative T cell(DN Treg cell) and CD4+CD25+ T cell ratios increased significantly from 2 days post MHV-3 infection in C3H/Hej mice,and CD3+CD4+CD8-,CD3+CD4-CD8+,CD3+CD4+CD25-and CD3+CD4-CD25+ T cell ratios decreased accordingly.In conclusion,the changes of virus titer and pathology in the livers of C3H/Hej mice post MHV-3 suggest their contribution to viral persistence.Further characterizations of DN Treg cells are that infection indicates that MHV-3 could induce the chronic inflammation in livers of C3H/Hej mice.The increase of the DN Treg cell and CD4+CD25+ T cell ratios in C3H/Hej mice post MHV-3 infection suggests that DN Treg cells and CD4+CD25+ T cells may both have important suppressive immunomodulation functions in the development of chronic viral hepatitis and have important roles in the virus persistent infection.Further characterizations of DNT cell and CD4+CD25+ T cell are under investigation.
文摘In the maximally-helicity-violating(MHV)configuration,tree-level single-trace Einstein-Yang-Mills(EYM)amplitudes with one or two gravitons have been shown to satisfy a formula in which each graviton splits into a pair of collinear gluons.In this study,we extend this formula to more general cases.We present a general formula that expresses tree-level single-trace MHV amplitudes in terms of pure gluon amplitudes.In this formula,each graviton turns into a pair of collinear gluons.