Figure 4.

The distribution of alcian blue-positive GRID cells changes during regeneration.

(a) Alcian blue-positive GRID cells were distributed through the dermis of the uninjured stump, proximal to the plane of amputation; however, these cells were not observed distal to the amputation plane during the early stages of blastema formation (amputation plane is indicated by the dashed line, the stump with blue GRID cells is to the left, dense collagen layer of the dermis is indicated by an asterisk, and the basal region of an early bud blastema is to the right). (b) Alcian blue-positive cells are observed at later stages of regeneration (late bud blastema), but are more readily observed in proximal regions (c) than in distal regions (d). GRID cells are visualized in (c,d) by 10E4 immunostaining (red). Scale bars: 100 μm.