Figure 7.

 CD44v3–v10 can present FGF-8 to limb mesenchymal cells. Limb bud mesenchymal cells were cocultured with UV-irradiated Namalwa cells expressing either CD44v3–v10 or CD44v8–v10 in the presence or absence of FGF-8. The Namalwa cells were then removed and mesenchymal cell proliferation was monitored by [³H]thymidine incorporation. Note that FGF-8 only exerts a significant proliferative effect when added together with Namalwa cells transfected with CD44v3–v10. Antibodies used: VFF18 (anti CD44v6), rabbit polyclonal “antihoming receptor” (anti CD44v3) and IM7 (anti CD44 N-term). Plotted cpm are the mean values of triplicate samples ± standard deviation. The absolute incorporation was highly dependent on cell density and data can only be compared within one series and relative to mesenchymal cells grown alone.