FL does not support the survival of osteoclasts isolated from rat bone.

Osteoclasts were extracted from the long bones of 2-day-old rats and sedimented onto coverslips for 20 minutes. Nonadherent cells were then washed off, and incubation continued for 1 hour or 24 hours with and without M-CSF or FL. *P < .05 versus 1 hour; a,P < .05 versus 24-hour control.