Title: Scientists Identify East African Bat Coronavirus Capable of Entering Human Cells

Scientists have identified an East African bat coronavirus capable of entering human cells through a previously unknown mechanism involving the human protein CEACAM6, according to new research published in Nature.

The virus, named Cardioderma cor coronavirus KY43 (CcCoV-KY43), was isolated from heart-nosed bats in Kenya and found to bind directly to CEACAM6, a glycoprotein widely expressed in human lung tissue. This receptor interaction enables the virus to enter human cells, marking a significant development in understanding zoonotic spillover potential.

Understanding the Virus and Its Mechanism

Using a computational approach that maximized phylogenetic diversity, researchers selected a subset of alphacoronavirus spike proteins for screening against broad coronavirus receptor libraries. While most selected spike proteins did not use established coronavirus receptors, the pseudotyped spike protein of CcCoV-KY43 demonstrated the ability to enter human cells.

Public Health Implications and Surveillance

Despite the virus’s ability to bind to human cells, immune surveillance studies using sera from individuals in the Taveta region of Kenya, where CcCoV-KY43 was identified, did not show significant evidence of recent spillover into the human population. This suggests that while the virus possesses the molecular capability to infect humans, ecological or biological barriers may currently prevent widespread transmission.

Broader Significance for Coronavirus Research

The discovery that alphacoronaviruses can use CEACAM6 as a receptor expands the known mechanisms by which coronaviruses enter human cells. Previously, SARS-CoV-2 was known to use ACE2, while other coronaviruses use receptors such as DPP4 or APN. This finding indicates that alphacoronaviruses, which include viruses commonly found in bats, have a broader receptor usage than previously understood.

Conclusion

The identification of CcCoV-KY43 and its use of CEACAM6 as a receptor highlights the importance of ongoing surveillance of bat coronaviruses and their potential to infect humans. While current evidence indicates no recent spillover in the Taveta region, the findings underscore the need for continued monitoring to detect any changes that could increase zoonotic risk. Understanding these mechanisms contributes to global efforts in pandemic preparedness by identifying potential threats before they emerge in human populations.