Granulocyte differentiation in methylcellulose culture. GM colonies were harvested individually and stained as in Fig 4. Results are shown as percent differentiated granulocytes (metamyelocytes, bands, and PMN) within the granulocytic lineage. The difference between wild-type controls and RARα1^−/−γ^−/− was significantly different (P < .05), whereas the difference with other groups was not significant.