Enhancement of SARS-CoV-2 vaccine-induced immunity by a Toll-like receptor 7 agonist adjuvant

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an enveloped positive-sense single-stranded RNA (ssRNA) virus responsible for the global COVID-19 pandemic. Although vaccines for SARS-CoV-2 have been developed and applied worldwide, research on vaccine adjuvant is lacking. Viral infections normally elicit a range of innate immune responses through the activation of pattern recognition receptors (PRRs), which have evolved to recognize a range of pathogen-associated molecular patterns (PAMPs). These innate immune responses, in turn, lead to the production of…