Effect of butyrate on γ-globin chain synthesis. Mononuclear cells from 3 patients with SCD (□, ▵, ◇) were cultured into BFU-E–derived colonies. (A) Effects of butyrate exposure in vitro on γ-globin chain synthesis in BFU-E cultured before initiation of butyrate infusions. (B) γ-Globin chain synthesis in BFU-E colonies cultured (without in vitro butyrate) from the same patients before and 24 hours after butyrate infusions. (C) Effects of butyrate exposure in vitro on γ-globin chain synthesis in BFU-E cultures initiated 24 hours after butyrate infusions in vivo. Data are expressed as percentageof γ-globin chain synthesis (ie, % γ/[γ + β]). Each data point represents the mean plus or minus 1 SD of triplicate cultures. Solid horizontal lines represent the mean value for every condition.