Infection of lymphoid tissues by pandemic respiratory viruses: SARS-CoV-2 and Influenza A H1N1

Abstract

Respiratory viruses are the most frequent human pathogens, and among them, influenza A viruses and coronaviruses stand out for their pandemic potential and high pathogenicity. Recently, a new betacoronavirus called SARS-CoV-2, has spread worldwide, with great social impact, and more than 4.5 million cases. SARS-CoV-2 causes severe respiratory syndrome and there is already evidence that it also affects multiple organs, including secondary lymphoid organs, with consequent lymphopenia. Influenza A viruses (IAV) cause annual seasonal influenza outbreaks, but they can also cause pandemics when new viral strains are introduced into human populations. Studies by our group have shown a high frequency of detection of respiratory viruses in general in tonsils of children with adenotonsillar hypertrophy, but without symptoms of acute respiratory infection, with IAV and endemic coronaviruses are among them. The data have already been confirmed by other groups, and indicate that respiratory viruses may remain for prolonged periods in the lymphoepithelial tissues of the upper respiratory tract. Therefore, it is reasonable to propose the hypothesis that the permanence of these viruses may play a role in their pathogenesis and be a potential source of transmission in the community. In this sense, the project aims to understand the viral pathogenesis of the IAV and SARS-CoV-2 viruses in lymphoid tissues. The goals of this proposal are to investigate the phenotypic and functional characterization of infected cells, production of cytokines and experimental infection of animal models with IAV and SARS-CoV-2, to assess the effects of infection on lymphoid cell functions, and prolonged infection in late times.