Visit to China
• The concern among people and the socioeconomic impact are high in China.
• China recognizes that it missed opportunities to address SARS more effectively and is now galvanized against it.
• Efforts include sequencing to enable molecular epidemiological testing, vaccine research, searching for an animal source, and building BL3 and BL4 labs.
S Gene Structure Resembles HIV gp 41
• Spike protein has two regions of alpha-helical structure with heptad repeats, like gp41 and other envelope virus structural proteins.
• Binding of gp120 to target host cells results in conformational changes that result in a hairpin formation, close approximation of viral and host membrane, and fusion.
• Peptides derived from repeat regions can inhibit virus entry and replication of HIV and other viruses; T-20, or Fuzeon, has recently been licensed as a drug.
• Evidence suggests that peptides lock the virus into an intermediate conformation, preventing fusion.
Testing peptides against SARS Coronavirus
• A qualitative CPE assay and a plaque assay in Vero cells have been used to test twelve peptides; five showed varying degrees of antiviral activity.
• Peptide therapeutics are difficult to make and are likely to be injectible rather than oral pills; development is rapid and they are generally not very toxic.
• Activity may be improved upon by optimizing the peptide sequence used.