 The first stage of the myeloid lineage is a granulocyte - monocyte progenitor (GMP), still an oligopotent progenitor, which then develops into unipotent cells that will later on form a population of granulocytes, as well as a population of monocytes.The first unipotent cell in granulopoiesis is a myeloblast.Committed granulopoiesis consists of maturation stages of unipotent cells.