ABSTRACT
The outbreaks caused by coronavirus (CoV) infections including severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS) and COVID-19 have emerged in recent years, posing a continued threat to public health. Highly pathogenic CoV infections usually induce a series of immune responses, including innate immunity, humoral immunity, cellular immunity and mucosal immunity. These responses not only are critical to suppressing and eliminating the invasion of viruses, but also play an important role in immunopathological changes and disease progression. A deep understanding of the dual roles of immune responses will help to elucidate the pathogenic mechanism of CoV and maintain the balance between immune protection and immunopathology, which will be conducive to the research and development of safe and effective CoV vaccines. This review summarized the dual roles of immune responses in highly pathogenic CoV infections and discussed the implications for the research and development of novel CoV vaccines.