Used in immunological research to study granulocyte-macrophage colony-stimulating factor (GM-CSF) signaling pathways. Binds GM-CSF with high affinity, enabling analysis of receptor-ligand interactions and downstream cellular responses. Employed in protein binding assays, surface plasmon resonance, and ELISA to quantify GM-CSF levels or block receptor activity. Supports development of therapeutic antibodies targeting inflammatory diseases, asthma, and certain cancers where GM-CSF signaling is dysregulated. The Fc tag facilitates detection, purification, and extends half-life in vivo when used in animal models.