Lymphatic Drainage-Promoting Effects by Engraftment of Artificial Lymphatic Vascular Tissue Based on Human Adipose Tissue-Derived Mesenchymal Stromal Cells in Mice

Figure 6

Histological distribution of regenerated lymphatic drainage. (a, b) The side views of LDI model mouse at three weeks after the popliteal transplantation of ASCLT. (a) ICG in vivo imaging. The routes of ICG-positive lymphatic drainage spread in the skin of the left hindlimb to abdomen. (b) Areas of tissue collected after FITC-dextran injection for histological analysis (shown in (c)–(n)). Red dashed line indicates the tissue including popliteal transplantation of ASCLT (graft). White dashed line indicates the area of the cutaneous tissue corresponding to the spread ICG-positive lymphatic drainage. (c) The section of popliteal area with ASCLT transplantation (HE staining). Asterisk () indicates the graft area. (d-f) High magnification images of (c) (corresponding to (d), (e), and (f) dashed boxes in (c)). (g-i) The corresponding parts of (d-f) in the serial section with immunostaining for FITC. (d, g) Images near the graft area. The lymphatic vessels (LV) in subcutaneous tissue are FITC-positive. Dermal muscle (DM) shows intense nonspecific fluorescence. (e) and (h) and (f) and (i) are images apart from the graft area. FITC-positive lymphatic vessels (LV) were located at subcutaneous tissue (SK) shallower than dermal muscle (DM). (j, k) Fluorescence microscopy of the skin tissue indicated in (b). The subcutaneous side of extracted skin is directly observed. (j) The arteries (A) and veins (V) are recognized by the presence of the blood in bright field. (k) The FITC-positive lymphatic vessels (LV) are visualized by the excitation of fluorescence. (l–n) The serial sections of cutaneous tissue. (l) HE staining. (m) Immunostaining for FITC and CD31. (n) Immunostaining for CD31 and mouse podoplanin. The lymphatic vessels (LV) at subcutaneous tissue shallower than dermal muscle (DM) show FITC and mouse podoplanin-positive (insets of (m) and (n)). V: blood vessels. The nuclei of the cells in the dark field image are visualized by DAPI (blue color).