Translocation of fibronectin-coated and uncoated latex beads in avian embryonic limb buds.

Latex beads were implanted into the chick wing bud to determine whether parameters other than active movement, for example matrix-driven translocation and growth of the limb bud, were responsible for the extensive re-allocation of myogenic cells that occurs during limb development. Latex beads were implanted into nine stage 20-24 Hamburger and Hamilton (H.H.) wing buds, and were allowed to develop for 3 days before examination. In all cases, it was found that most of the latex beads (86.57% +/- 11.4%) were confined to the implantation site. A small percentage of beads was observed in the connective and myogenic regions proximal and distal to the graft side. In general the displacement of these beads was relatively short, although in one specimen a few beads were translocated to regions as far as the autopod. The surface of the latex beads was also coated with fibronectin prior to transplantation, to ascertain whether the extracellular matrix can influence the translocation of beads within the limb bud. Ten specimens were examined, and as for uncoated latex beads, most of the fibronectin-coated beads (87.14% +/- 11.67%) were contained within the transplantation site. Again a small percentage of beads was found in the connective and myogenic but not in the chondrogenic tissues proximal and distal to the graft side. In one specimen fibronectin-coated beads were translocated to regions in the autopod, but in general, bead displacement was relatively short. In sum, latex beads can not move to any great extent within the limb bud, and the coating of these beads with fibronectin did not influence bead translocation.