Additionally, in order to enhance specificity, the monoclonal antibody, which was obtained by immunizing Balb/C mice with free peptide H26R corresponding to the second extracellular loop of the human β1-AR, and had the same biological effect with β1-AAIgGs isolated from heart failure patients (Fig. S3), was used to serve as positive control (Fig. S1A). This evidence concerns the gene ADRB1 and heart failure.