VEGF-C gene therapy augments postnatal lymphangiogenesis and ameliorates secondary lymphedema
J. Clin. Invest. Young-sup Yoon, et al. 111:717 doi:10.1172/JCI15830 [Go to this article.]

Figure 5
(a–j) phVEGF-C induces proliferation of lymphatic endothelial cells. Double immunohistochemistry using LYVE-1 and Ki-67 in active lymphangiogenesis site from skin sections. In a, d, and g, LYVE-1 staining of lymphatic vessels (arrows) in the dermis. In b, e, and h, green fluorescence (white arrowheads) depicts the nuclear staining of Ki-67. In c, f, and i, double fluorescence (yellow arrowheads) demonstrates Ki-67⁺ nuclei (green) in lymphatic vessels (red). Lymphatic vessels in normal skin (c) are shown negative for Ki-67. In the LacZ group, some of the lymphatic vessels contain Ki-67⁺ nuclei (f). White arrows in f show Ki-67^– lymphatic vessels. In phVEGF-C–transfected skin, most of the LYVE-1–positive lymphatic vessels are positive for Ki-67 (i), indicating that active cell division occurs in the lymphatic vessels. (j) Number of Ki-67⁺ nuclei are 2.5 times higher in the VEGF-C group. *P < 0.01 compared with normal; **P < 0.01 compared with saline and LacZ. Scale bar, 100 μm. (k–u) phVEGF-C does not increase capillary density in two animal models of lymphedema. Immunohistochemistry with CD31 (PECAM-1) in a rabbit ear (k–n) and a mouse tail (p–t) model of lymphedema on skin sections from the normal (k and p), saline (l and q), LacZ (m and r), VEGF-C (n and s), and VEGF₁₆₅ (t) groups. Vascular endothelial cells are stained red (black arrows). o and u show quantification of capillary density. Only the VEGF₁₆₅ group in the mouse tail model demonstrated significantly higher capillary density than the other groups. *P < 0.01 vs. saline, LacZ, and VEGF-C. Scale bar, 100 μm.