I'm looking for either a vendor or a kind soul who knows where I could get my hands on the KS-4 murine pre-osteoblast cell line or something similar. I'm familiar with the MC3T3-E1 line, but those cells are too far down the OB differentiation pathway for our purposes. I've also considered C2C12 cells, but the fact that they require BMP2 to differentiate to osteoblasts presents a problem in our in vitro system. Any suggestions?