Immune memory from SARS-CoV-2 infection in hamsters provides variant-independent protection but still allows virus transmission

Horiuchi and Oishi et al.

Sci. Immunology 26/10/2021


SARS-CoV-2 has caused significant morbidity and mortality across the globe. As the virus spreads, new variants are arising that show enhanced capacity to bypass pre-existing immunity. To understand the memory response to SARS-CoV-2, here we monitored SARS-CoV-2-specific T and B cells in a longitudinal study of infected and recovered golden hamsters. We demonstrated that engagement of the innate immune system following SARS-CoV-2 infection was delayed but was followed by a pronounced adaptive response. Moreover, T cell adoptive transfer conferred a reduction in virus levels and rapid induction of SARS-CoV-2-specific B cells demonstrating both lymphocyte populations contributed to the overall response. Re-infection of recovered animals with a SARS-CoV-2 variant of concern showed that SARS-CoV-2-specific T and B cells could effectively control the infection which associated with the rapid induction of neutralizing antibodies but failed to block transmission to both naïve and seroconverted animals. These data suggest that the adaptive immune response to SARS-CoV-2 is sufficient to provide protection to the host, independent of the emergence of novel variants.