Severe community acquired adenovirus pneumonia in an immunocompetent host successfully treated with IV Cidofovir

Study on the Changes and Significance of Immune State and Cycokines in Children with Adenovirus Pneumonia

Objective. To observe the difference between peripheral blood T lymphocytes subsets and cycokines in children with severe adenovirus pneumonia and nonsevere adenovirus pneumonia, and to investigate their clinical value in the prognosis of severe pneumonia. Methods. 215 children with adenovirus pneumonia and 30 healthy volunteers (which was set as the control group) in our hospital from January 2017 to May 2019 were enrolled in the study. There were 47 children with severe pneumonia in the severe group and 168 nonsevere pneumonia children in the nonsevere group. The flow cytometry and ELISA methods were used to detect the serum levels of CD3+, CD4+, CD8+ T cells and interleukin-2 (IL-2), IL-4, IL-6, IL-10, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ). Results. (1) The levels of CD3 (%) T cells, CD4 (%) T cells, and CD4/CD8 ratio values of children with adenovirus pneumonia were lower than these of normal children ( $P<0.05$ ). And the levels of CD3 (%) T cells, CD4 (%) T cells, and CD4/CD8 ratio values of children in the severe group were lower than these of children in the nonsevere group ( $P<0.05$ ). (2) The levels of IL-2, IL-6, IL-10, TNF-α, and IFN-γ values of children with adenovirus pneumonia were lower than these of normal children ( $P<0.05$ ). And the levels of IL-2, IL-6, IL-10, TNF-α, and IFN-γ of children in the severe group were higher than these of children in the nonsevere group ( $P<0.05$ ). (3) Among the 47 children with severe adenoviral pneumonia, 39 received systematic treatment in our hospital. According to the treatment effect, 39 children were divided into the effective group (n = 25) and the ineffective group (n = 14). (4) The CD3 (%), CD4 (%), and CD4/CD8 ratios of the children in the effective group were higher than those in the ineffective group ( $P<0.05$ ). (5) The levels of IL-2, IL-6, IL-10, TNF-α, and IFN-γ in the effective group were lower than those in the ineffective group ( $P<0.05$ ). Conclusion. The immunophenotype of peripheral blood T lymphocytes and cycokines could be helpful to judge the severity of adenovirus pneumonia, which could be used as the objective indexes to evaluate the prognosis of children with severe adenovirus pneumonia.

Chinese tree shrew: a permissive model for in vitro and in vivo replication of human adenovirus species B

Human adenovirus (HAdV) species B can cause severe acute respiratory diseases. However, the researches to combat this infection have been hampered by the lack of an animal model permissive to the virus. Here, we report in vitro and in vivo HAdV species B infections of tree shrews, the closest relative of primates. HAdV-3, -7, -14, and -55 efficiently replicated in primary cell cultures. After intranasal inoculation of tree shrews with HAdV-55, the viral replication in the oropharyngeal region remained high until day 5 post-infection and was still detected until day 12. HAdV-55 in the lung or turbinate bone tissues reached the highest levels between days 3 and 5 post-infection, which indicated viral replication in the upper and lower respiratory tracts. HAdV-55 infection caused severe interstitial pneumonia in the animal. IL-8, IL-10, IL-17A, and IFN-γ expression in the peripheral blood mononuclear cells from infected animals was up-regulated. The pre-vaccination with HAdV-55 cleared the virus faster in the respiratory tract, mitigated lung pathological changes. Finally, HAdV-55 infection was propagated among tree shrews. Our study demonstrated that the tree shrew is a permissive animal model for HAdV species B infection and may serve as a valuable platform for testing multiple anti-viral treatments.