Figure 5
Newtic1-expressing erythrocytes do not contribute to larval limb blastema. (a) Representative image showing immunoreactivity in the blastema of the forearm in swimming larvae ~3 months old (stage 57–58; n = 3). Line: amputation plane. In contrast to adult limbs (Fig. 4), Newtic1 immunoreactivity was hardly observed in mesenchymal cells in the blastema, while a large number of fibrous cells were labeled with vimentin antibody. Note that in larval limbs, Newtic1 antibody labeled cells of gland-like structures along the skin (even on the blastema), and vimentin antibody labeled many fibrous cells similar to fibroblasts. Topro-3 (TP3): nucleus. Scale bar, 200 μm. (b) A section showing a large blood vessel (dotted line) in the blastema. We were unable to find Newtic1-immunoreactive (Newtic1+) cells in blood capillaries/vessels in the blastema (n = 3). Scale bar, 100 μm. (c) Newtic1+ erythrocytes in swimming larvae ~3 months old (stage 57–58). Larval erythrocytes (longer axis: ~15 μm) were about half the size of those from adults. Gathering of Newtic1+ erythrocytes was rarely observed in normal blood (2 of 26 sections from 9 limbs). These cells were not associated with either vimentin-immunoreactive cells or cells such as monocytes. Scale bar, 100 μm.
