Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) is a cytokine that plays a key role in the immune/inflammatory cascade. The protein functions as a white blood cell growth factor, stimulating stem cells to produce granulocytes and monocytes. GM-CSF carries out this function by activating signaling pathways via a cell surface receptor known as the Colony Stimulating Factor 2 Receptor. This is a heterodimeric protein made up of a ligand-binding alpha subunit, encoded by the CSF2RA gene, and an affinity enhancing beta subunit, encoded by the CSF2RB gene.
Due to its role in the immune system, mutations in the CSF2RA gene can have strong pathological consequences. The gene has been implicated in Surfactant Metabolism Dysfunction, Pulmonary, 4 (SMDP4), a rare interstitial lung disorder characterized by respiratory distress and surfactant protein exudate accumulation in the alveoli.