Using a perfusion de
cellularization proto
col, we developed a de
cellularized skin/adipose tissue flap (DSAF)
comprising extra
cellular matrix (ECM) and inta
ct vas
culature. Our DSAF had a dominant vas
cular pedi
cle, mi
cro
cir
culatory vas
cularity, and a sensory nerve network and retained three-dimensional (3D) nanofibrous stru
ctures well. DSAF, whi
ch was
composed of
collagen and laminin with well-preserved growth fa
ctors (e.g., vas
cular endothelial growth fa
ctor, basi
c fibroblast growth fa
ctor), was su
ccessfully repopulated with human adipose-derived stem
cells (hASCs) and human umbili
cal vein endothelial
cells (HUVECs), whi
ch integrated with DSAF and formed 3D aggregates and vessel-like stru
ctures
in vitro. We used mi
crosurgery te
chniques to re-anastomose the re
cellularized DSAF into nude rats.
In vivo, the engineered flap
constru
ct underwent neovas
cularization and
constru
ctive remodeling, whi
ch was
chara
cterized by the predominant infiltration of M2 ma
crophages and signifi
cant adipose tissue formation at 3 months postoperatively. Our results indi
cate that DSAF
co-
cultured with hASCs and HUVECs is a promising platform for vas
cularized soft tissue flap engineering. This platform is not limited by the flap size, as the entire
constru
ct
can be immediately perfused by the re
cellularized vas
cular network following simple re-integration into the host using
conventional mi
crosurgi
cal te
chniques.
c_2">Statement of Significance
Significant soft tissue loss resulting from traumatic injury or tumor resection often requires surgical reconstruction using autologous soft tissue flaps. However, the limited availability of qualitative autologous flaps as well as the donor site morbidity significantly limits this approach. Engineered soft tissue flap grafts may offer a clinically relevant alternative to the autologous flap tissue. In this study, we engineered vascularized soft tissue free flap by using skin/adipose flap extracellular matrix scaffold (DSAF) in combination with multiple types of human cells. Following vascular reanastomosis in the recipient site, the engineered products successful regenerated large-scale fat tissue in vivo. This approach may provide a translatable platform for composite soft tissue free flap engineering for microsurgical reconstruction.