Lessons for COVID-19 Immunity from Other Coronavirus Infections

Abstract

A key goal to controlling coronavirus disease 2019 (COVID-19) is developing an effective vaccine. Development of a vaccine requires knowledge of what constitutes a protective immune response and also features that might be pathogenic. Protective and pathogenic aspects of the response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are not well understood, partly because the virus has infected humans for only 6 months. However, insight into coronavirus immunity can be informed by previous studies of immune responses to non-human coronaviruses, common cold coronaviruses, and SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV). Here, we review the literature describing these responses and discuss their relevance to the SARS-CoV-2 immune response.

Figure 1

Genomic Organization and Virion Structure (A) Schematic of the 30-kb SARS-CoV-2 genome. The first two-thirds of CoV genomes encode a polyprotein that is cleaved into constituent nonstructural proteins involved in replication and immune evasion, while the remaining one-third encodes the four main structural proteins (S, E, M, and N), along with accessory proteins. (B) Schematic representation of a CoV virion. gRNA, genomic RNA.

Figure 2

Human Coronavirus Tropism and Longevity of Immune Responses Schematic depicting sites of replication of human coronaviruses (A) and schematic of longevity of immune responses to common cold coronaviruses, SARS-CoV, and MERS-CoV (B) (not drawn to scale). Data not available for antibody longevity in patients following mild disease caused by SARS-CoV.