Fig. 9.
Effects of ATRA on the early phase of mast cell development.
Five thousand 10-week cultured mast cells were plated per dish containing serum-deprived methylcellulose culture medium supplemented with SCF, SCF+ATRA, SCF+IL-4, or SCF+IL-6. After 2 weeks, aggregates consisting of 30 or more cells were scored as mast cell colonies, and those of 10 to 29 cells as mast cell clusters. SCF, 100 ng/mL; ATRA, 10−10 mol/L to 10−7 mol/L; IL-4, 20 ng/mL; IL-6, 50 ng/mL. Numbers of mast cell colonies (black bars) and mast cell clusters (gray bars) are shown. The results shown are from 1 representative experiment of 3. Similar results were obtained in the other 2 experiments. Significantly different from SCF alone (*P < .002, **P < .0001).
