This paper defines gene products that mediate entry of a newly discovered virus, the SARS coronavirus (SARS-CoV), and defines the mechanism by which it enters cells. It also shows that the virus attaches to cells not only through its primary receptor, ACE2, defined by the Farzan lab, but through an attachment factor, DC-SIGN or a similarly related molecule, which allows it to attach to dendritic cells, which promote cell-mediated viral transfer. The paper describes both new methods and original information which have been helpful in the development of vaccine candidates and medical interventions against this emerging infectious disease.

This paper described new discoveries which help us understand how and where SARS-CoV might infect humans. It also described a new method that can be used to effectively evaluate the neutralization sensitivity of the virus and therefore optimize the efficacy of SARS-CoV vaccine candidates. The paper described the use of lentiviral and retroviral vector pseudotyping with the spike glycoprotein of SARS-CoV to detect infection and therefore to quantitate the presence of neutralizing antibodies.

The paper defines the proteins in the SARS coronavirus that are responsible for infecting cells and shows that an endosomal pathway is used by the virus to enter. The findings also point to strategies for the development of antiviral antibodies and drugs, as well as vaccines. The new information described in this paper certainly can help us understand the nature of SARS coronavirus infection and will help in vaccine development.

When the SARS outbreak was first recognized the virus responsible for the disease was discovered, we began efforts to develop a vaccine, which required a more fundamental understanding of how the virus functions.