Comparison of osteoclast development in liquid culture and in methylcellulose medium.

(A) Time course of the change in frequency of TRAP⁺ cells when c-Fms⁺RANK⁻ cells were cultured with M-CSF and sRANKL in liquid (●) or methylcellulose medium (○) for 6 days. (B) Colonies cultured with M-CSF and sRANKL in methylcellulose were replated into liquid (●) or methylcellulose (○) and cultured with M-CSF and sRANKL for 6 days. Note that the frequency of TRAP⁺ cells increased in liquid culture but not in methylcellulose culture. (C) Colonies cultured with M-CSF alone were replated into liquid (●) or methylcellulose (○) individually and further cultured with M-CSF and sRANKL. Note that the cells in methylcellulose medium cultured with M-CSF alone still had a potency to differentiate into TRAP⁺ cells, especially in liquid culture.