Small Blood Vessel Engineering

Abstract

SummaryTissue engineering has attracted wide interest as a potential method to alleviate the shortage of transplantable organs (1). To date, almost all of the successfully engineered tissues/organs have relatively thin and/or avascular structures [e.g., skin (2), cartilage (3), and bladder (4)], where postimplantation vascularization from the host (angiogenesis) is sufficient to meet the implant's demand for oxygen and nutrients. Vascularization remains a critical obstacle impeding attempts to engineer thicker, metabolically demanding organs, such as heart and liver. One approach in vascularizing an engineered tissue is to add the cellular components of blood vessels (endothelial and perivascular cells) directly to the tissue-engineered construct. We have shown that coimplanting endothelial cells and perivascular cells in a scaffold in vivo can lead to the formation of a vascular network that anastomoses to the host circulatory system. The engineered vessels are stable and functional, and they persist for more than 1 year in vivo. This approach may potentially lead to the creation of a well-vascularized-engineered tissue.

Generation of functionally competent and durable engineered blood vessels from human induced pluripotent stem cells

“…S9) with 10T1/2 MPCs in vivo using the tissue-engineered model in the cranial window of SCID mice (26,27). We found that T1D-iPS cell-derived ECs could generate a functional vasculature within 2 wk of coimplantation.…”

Geometrically Controlled Endothelial Tubulogenesis in Micropatterned Gels

“…[5][6][7] An alternate approach involves seeding vascular precursors into these constructs before implantation in the hope that these cells will receive the appropriate cues to form vessels in vitro or in vivo. [8][9][10][11] A third approach involves preforming constructs containing endothelial tubules and promoting integration of construct vessels with in vivo vasculature after implantation. 12,13 Several recent studies suggest that incorporating cells or preexisting endothelial networks may accelerate the vascularization of an implant, thereby improving the likelihood for long-term implant survival.…”

“…12,13 Several recent studies suggest that incorporating cells or preexisting endothelial networks may accelerate the vascularization of an implant, thereby improving the likelihood for long-term implant survival. 10,13,14 However, the vascular networks that form when endothelial cells are implanted in vivo are typically randomly distributed in space, making it difficult to recapitulate the vasculature of organs such as the liver that are comprised of multiple cell types precisely distributed around a complex organized vascular network. Consequently, novel methods to spatially pattern endothelial cells and promote vascularization are needed for such applications.…”

Evolution and Trends in Reconstructive Facial Surgery: An Update

“…Stem cells may overcome these deficiencies of autologous end-stage cells transplantation. Because they are capable of multiple population doublings, therefore potentially serving as a replenishable source for facial tissue reconstruction [71,72,73].…”