Fig. 6. Mobilization of CECs/EPCs in parabiosis (part 2). (A) An
endothelin 1-producing CHO nodule (No), 5 days after cellular implantation
onto a `parabiotic' chick CAM. Capillaries are organized in a spoke-wheel
formation (*) converging to the nodule. Scale bar: 1 mm. (B)
The nodule (No) is wrapped in the CAM, and QH1+ECs (arrows)
participate in its vascularization. Scale bar: 160 µm. (C) Higher
magnification of QH1+ECs invading the nodule (arrows): one cell is
in a capillary endothelium (*), two are located interstitially.
Scale bar: 20 µm. (D-G) `Parabiotic' chick CAM 4 days after VEGF (D)
or PBS (E) treatment: increased vessel branching (*) is apparent in
D compared with E. Scale bar: 1.5 mm. (F,G) The vessel density (*)
is higher in VEGF-treated (F) than in PBS-treated (G) CAM. Although the
inflammatory response leads to an invasion of a great number of
QH1+HCs (brown dots) in both treatments, the number of
QH1+ECs (arrows) is similar. Scale bar: 90 µm.
(H,I) Mobilization in absence of bone marrow: wounds on
`parabiotic' chick wings (H) and grafts of chick limb buds onto `parabiotic'
chick CAM (I) lead to an invasion of QH1+ECs (arrows) and
QH1+HCs (arrowheads). ca, cartilage. Scale bars: 90 µm in H; 70
µm in I.