title: Repair of an articular cartilage defect using adipose-derived stem cells loaded on a polyelectrolyte complex scaffold based on poly(l-glutamic acid) and chitosan.
abstract: As a synthetic polypeptide water-soluble poly(l-glutamic acid) (PLGA) was designed to fabricate scaffolds for cartilage tissue engineering. Chitosan (CHI) has been employed as a physical cross-linking component in the construction of scaffolds. PLGA/CHI scaffolds act as sponges with a swelling ratio of 760±45% (mass%), showing promising biocompatibility and biodegradation. Autologous adipose-derived stem cells (ASCs) were expanded and seeded on PLGA/CHI scaffolds, ASC/scaffold constructs were then subjected to chondrogenic induction in vitro for 2weeks. The results showed that PLGA/CHI scaffolds could effectively support ASC adherence, proliferation and chondrogenic differentiation. The ASCs/scaffold constructs were then transplanted to repair full thickness articular cartilage defects (4mm in diameter, to the depth of subchondral bone) created in rabbit femur trochlea. Histological observations found that articular defects were covered with newly formed cartilage 6weeks post-implantation. After 12weeks the regenerated cartilage had integrated well with the surrounding native cartilage and subchondral bone. Toluidine blue and immunohistochemical staining confirmed similar accumulation of glycosaminoglycans and type II collagen in engineered cartilage as in native cartilage 12weeks post-implantation. The result was further supported by quantitative analysis of extracellular matrix deposition. The compressive modulus of the engineered cartilage increased significantly from 30% of that of normal cartilage at 6weeks to 83% at 12weeks. Cyto-nanoindentation also showed analogous biomechanical behavior of the engineered cartilage to that of native cartilage. The results of the present study thus demonstrate the potentiality of PLGA/CHI scaffolds in cartilage tissue engineering.
authors.affiliation: Department of Polymer Materials, Shanghai University, 20 Chengzhong Street, Shanghai 201800, People's Republic of China.
authors.forename: Kunxi
authors.initials: K
authors.lastname: Zhang
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
authors.forename: Shifeng
authors.initials: S
authors.lastname: Yan
authors.forename: Lunli
authors.initials: L
authors.lastname: Gong
authors.forename: Jia
authors.initials: J
authors.lastname: Wang
authors.forename: Xuesi
authors.initials: X
authors.lastname: Chen
authors.forename: Lei
authors.initials: L
authors.lastname: Cui
authors.forename: Jingbo
authors.initials: J
authors.lastname: Yin
mesh_terms: D000273:Adipose Tissue / Q000166:cytology; D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D048271:Chitosan / Q000737:chemistry*; D020219:Chondrogenesis; D004573:Electrolytes / Q000737:chemistry; D017102:Fracture Healing; D050724:Fractures, Cartilage / Q000473:pathology / Q000601:surgery*; D011099:Polyglutamic Acid / Q000737:chemistry*; D011817:Rabbits; D033581:Stem Cell Transplantation / Q000295:instrumentation*; D013234:Stem Cells / Q000166:cytology*; D054457:Tissue Scaffolds; D016896:Treatment Outcome
chemical_list: D004573:Electrolytes; D011099:Polyglutamic Acid; D048271:Chitosan