Development of antiviral synbodies against A/California/07/2009 pdm09 H1N1, a model unknown virus. (A) Relative fluorescence (RFU) for each peptide from binding of pdm09 H1N1. Values represent mean ± s.e.m. for six replicate spots per peptide. Background binding was measured in empty spots (Bkgd.) and peptide hits had mean binding that was significantly higher (p < 0.01) while a negative control peptide (p94) did not. (B) Inhibition of pdm09 H1N1 hemagglutination by synbodies. Error bars represent the standard error from replicate assays. (C) Plaque reduction of pdm09 H1N1 infected MDCK cells with candidate synbodies. A neutralizing pdm09 H1N1 mAb was used as a positive control and three HAI inhibiting (p125-p125, p125-p149, p227-p227) and a non-HAI inhibiting synbody (p151-p151) were tested. Error bars represent the standard error from replicate assays.