Fig 4. Binding of phage to IL-23 and W137A, L141A, and K145A variants.

Binding of peptide-phage to wild-type IL-23 was compared to three p19 alanine variants including W137A, L141A, and K145A using flow cytometry. Peptides with less than 10% positive signal (chosen arbitrarily) were eliminated. Peptides with considerable reduction in binding to W137A variant compare to wild type were considered as potential blockers and are marked by an arrow (n = 2). Fab and naked phage was used as controls.