Role of CD44v3 in HA-induced FN production by HCs. Panel A shows a representative FACS profile of HCs stained for CD44v3 (—) using a triple-layer technique identical to that used for FGFR-1 detection (- - - -; IgG2b class-specific control). In panel B, HCs were cultured on BSA-coated or HA-coated plastic and FN production at 24 hours was measured by an ELISA. In each case, the effect on FN production of coincubation with either anti-CD44v3 mAbs (or with IgG2b class-specific control, which had no effect; not shown) or with heparitinase was tested. In panel C, the effect of the anti-CD44v3 mAbs on HA-induced FGF-2 production (as estimated by ELISA) was measured.