The original antibody was isolated from a human Fab phage display library by panning against chimeric HHM-ST2L construct with the biotinylated antigen captured on streptavidin-coated magnetic beads. Phage selections were performed for three rounds followed by screening by ELISA for Fab binding to hST2L-Fc protein. The selected Fab was affinity matured and converted to a human IgG1 format.