The clotting and staining of methylcellulose cultures of human hemopoietic cells.

We describe a technique for clotting, fixing and staining methylcellulose cultures of human hemopoietic progenitor cells. The entire cellular population of a 1-ml culture in a 35-mm plastic petri dish can be recovered and preserved permanently with this method. The technique also provides the opportunity for distinguishing between pure erythroid and mixed colonies, for examining cellular morphology without tediously picking individual colonies, and for terminating cultures on the appropriate day without the necessity of scoring on that same day.