title: Tissue formation and vascularization in anatomically shaped human joint condyle ectopically in vivo.
abstract: Scale-up of bioengineered grafts toward clinical applications is a challenge in regenerative medicine. Here, we report tissue formation and vascularization of anatomically shaped human tibial condyles ectopically with a dimension of 20 x 15 x 15 mm(3). A composite of poly-epsilon-caprolactone and hydroxyapatite was fabricated using layer deposition of three-dimensional interlaid strands with interconnecting microchannels (400 microm) and seeded with human bone marrow stem cells (hMSCs) with or without osteogenic differentiation. An overlaying layer (1 mm deep) of poly(ethylene glycol)-based hydrogel encapsulating hMSCs or hMSC-derived chondrocytes was molded into anatomic shape and anchored into microchannels by gel infusion. After 6 weeks of subcutaneous implantation in athymic rats, hMSCs generated not only significantly more blood vessels, but also significantly larger-diameter vessels than hMSC-derived osteoblasts, although hMSC-derived osteoblasts yielded mineralized tissue in microchannels. Chondrocytes in safranin-O-positive glycosaminoglycan matrix were present in the cartilage layer seeded with hMSC-derived chondrogenic cells, although significantly more cells were present in the cartilage layer seeded with hMSCs than hMSC-derived chondrocytes. Together, MSCs elaborate substantially more angiogenesis, whereas their progenies yield corresponding differentiated tissue phenotypes. Scale up is probable by incorporating a combination of stem cells and their progenies in repeating modules of internal microchannels.
authors: Tissue Engineering and Regenerative Medicine Laboratory, Columbia University Medical Center, New York, New York 10032, USA.
authors: Chang H
authors: CH
authors: Lee
authors: Nicholas W
authors: NW
authors: Marion
authors: Scott
authors: S
authors: Hollister
authors: Jeremy J
authors: JJ
authors: Mao
mesh_terms: D000328:Adult; D000818:Animals; D057005:Bioengineering / Q000379:methods*; D002113:Calcification, Physiologic; D019902:Chondrocytes / Q000166:cytology; D020219:Chondrogenesis; D006801:Humans; D007150:Immunohistochemistry; D020007:Implants, Experimental; D007596:Joints / Q000033:anatomy & histology* / Q000098:blood supply* / Q000637:transplantation; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism; D018919:Neovascularization, Physiologic; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism; D051381:Rats; D013977:Tibia / Q000033:anatomy & histology* / Q000098:blood supply* / Q000637:transplantation; D054457:Tissue Scaffolds / Q000737:chemistry