Navigation lymphatic supermicrosurgery, in which lymphatic vessels are visualized with intraoperative microscopic ICG lymphography, allows a lymphatic supermicrosurgeon to find and dissect lymphatic vessels earlier and facilitates successful performance of lymphaticovenular anastomosis.

In SM-LVA surgery, a vein can be harvested from another surgical field without additional invasiveness and is useful for bridging a lymphatic vessel and a distant vein.

The superior gluteal artery perforator (SGAP) flap is a widely used flap for sacral reconstruction. However, it is non‐sensate flap and sensory loss is one of the most important risk factors for pressure ulcer development and recurrence; therefore, a sensate SGAP flap would be ideal for the reconstruction. Because the upper buttock is innervated by the superior cluneal nerves (SCNs) which originate from Th11 to L4, a sensate SGAP flap based on SCNs is anatomically possible. Herein, we present a novel sensate SGAP flap based on SCNs for reconstruction of sacral defects. Two patients with a sacral defect underwent reconstruction using a sensate SGAP flap (53 and 56 years old, both men). Diagnoses were sacral spindle cell sarcoma and sacral pressure ulcer. The defect sizes were 16 × 13 and 12 × 11 cm. The flap was designed based on the locations of SCNs which are commonly located at 6–8 cm lateral from the midline at the iliac crest. Flap sizes were 16 × 9 and 15 × 13 cm, respectively. The flaps survived completely in both cases. Flap sensation was observed immediately after surgery except in flap margins. However, sensory recovery occurred in these areas as well several months postoperatively. None of the patients developed postoperative pressure ulcers during the follow‐up period of 37 and 13 months. This method may preserve flap sensation and therefore can contribute to reducing the risk of postoperative pressure ulcers and could be a useful option for sacral reconstruction.

The adeno-associated virus (AAV) is a potent vector for in vivo gene transduction and local therapeutic applications of AAVs, such as for skin ulcers, are expected. Localization of gene expression is important for the safety and efficiency of genetic therapies. We hypothesized that gene expression could be localized by designing biomaterials using poly(ethylene glycol) (PEG) as a carrier. Here we show one of the designed PEG carriers effectively localized gene expression on the ulcer surface and reduced off-target effects in the deep skin layer and the liver, as a representative organ to assess distant off-target effects, using a mouse skin ulcer model. The dissolution dynamics resulted in localization of the AAV gene transduction. The designed PEG carrier may be useful for in vivo gene therapies using AAVs, especially for localized expression.

Summary ParagraphMammalian skin appendages, such as hair follicles and sweat glands, are complex mini-organs formed during skin development1, 2. As wounds heal, the resulting scar tissue lacks skin appendages. The clinical regeneration of skin appendages is an ongoing challenge3, 4. Skin epithelial tissues have been regeneratedin vivoby cellular reprogramming5, 6, but thede novogeneration of skin appendages has not previously been achieved. Here, we show that transplantation of a type of epithelial cell and two types of mesenchymal cells, reprogrammed from adult mouse subcutaneous mesenchymal cells to mimic developing skin cells, resulted in the generation of skin-appendage-like structures. Furthermore, with the development of a new AAV serotype,in vivoreprogramming of wound-resident cells with the same reprogramming factors generates skin withde novoappendages in adult mice. These findings may provide new therapeutic avenues for skin regeneration and frequent aging-associated skin appendage disorders, such as hair loss and dry skin, and may extend to other tissues and organs. This study also provides the potential forde novogeneration of complex organsin vivo.