A recent study published in "PLOS Pathogens" demonstrated that although spike proteins from the Khosta-2 virus (a sarbecovirus discovered in Russia) were capable of infecting cells using the same entry ways as human pathogens, it was resistant to being neutralized by serum from people who had received the SARS-CoV-2 vaccine.

SARS-CoV outbreaks and the current coronavirus disease pandemic have been triggered by the spillover of sarbecoviruses from animals to people. A wide array of animal sarbecoviruses have been found as a result of research into the origins of SARS-CoV-1 and SARS-CoV-2. Most of them are only distantly related to recognized human pathogens and do not contaminate human cells.

The sarbecovirus's receptor binding domain (RBD) interacts with receptor molecules on surface of host cells. This, in turn, results in the mediation of cell invasion. This study investigated the serological cross-reactivity and receptor tropism for RBDs from 2 sarbecoviruses identified in the Russian horseshoe bats. Despite the fact that these two viruses belong to a different viral lineage than SARS-CoV-1 and SARS-CoV-2, the RBD from one of them, Khosta 2, was able to exploit human Angiotensin-converting enzyme 2 (ACE2) to promote cell entrance.

The viral pseudotypes with a recombinant viral chimeric spike that encodes for Khosta 2 RBD were found to be resistant to both SARS-CoV-2 monoclonal antibodies and serum from people who had received the SARS-CoV-2 vaccine. Hence, sarbecoviruses spreading in wildlife outside of Asia constitute a hazard to the general public's health as well as continuing SARS-CoV-2 immunization efforts. The findings from this study emphasized the urgent need to continue the development of novel and broader-protecting sarbecovirus vaccines.