ðə sˈiːkwəns ʌv hjˈuːmən dʒˌiːˈɛmsˌiːˌɛsˈɛf wʌz fˈɜːst aɪdˈɛntᵻfˌaɪd ɪn nˈaɪntiːnhˈʌndɹɪd ˈeɪɾi fˈaɪv ænd sˈuːn θɹˈiː ɹˌiːkˈɑːmɪnbənt hjˈuːmən dʒˌiːˈɛmsˌiːˌɛsˈɛfs wɜː pɹədˈuːst, wˈʌn ɪn bæktˈɪɹiə, wˈʌn ɪn mæmˈeɪliən sˈɛlz, ænd wˈʌn ɪn jˈiːst; ɪmˈʌnɛks dɪvˈɛləpt dʒˌiːˈɛmsˌiːˌɛsˈɛf mˌænjuːfˈæktʃɚd ɪn jˈiːst ˌɪntʊ lˈuːkaɪn.
The sequence of human GM-CSF was first identified in 1985 and soon three recominbant human GM-CSFs were produced, one in bacteria, one in mammalian cells, and one in yeast; Immunex developed GM-CSF manufactured in yeast into Leukine.