Xin Wang1, Xiongbo Song1, Tao Li1, Jiajia Chen2, Guotao Cheng3, Liu Yang1, Cheng Chen1. 1. Center for Joint Surgery, Southwest Hospital, Third Military Medical University, Chongqing, China. 2. Biomedical Analysis Center, Third Military Medical University, Chongqing, China. 3. College of Biotechnology, Southwest University, Chongqing, China.
Abstract
BACKGROUND: Recruitment of endogenous stem cells has been considered an alternative to cell injection/implantation in articular cartilage repair. PURPOSE: (1) To develop a cartilage tissue-engineering scaffold with clinically available biomaterials and functionalize the scaffold with an aptamer (Apt19s) that specifically recognizes pluripotent stem cells. (2) To determine whether this scaffold could recruit joint-resident mesenchymal stem cells (MSCs) when implanted into an osteochondral defect in a rabbit model and to examine the effects of cartilage regeneration. STUDY DESIGN: Controlled laboratory study. METHODS: The reinforced scaffold was fabricated by embedding a silk fibroin sponge into silk fibroin/hyaluronic acid-tyramine hydrogel and characterized in vitro. A cylindrical osteochondral defect (3.2 mm wide × 4 mm deep) was created in the trochlear grooves of rabbit knees. The rabbits were randomly assigned into 3 groups: Apt19s-functionalized scaffold group, scaffold-only group, and control group. Animals were sacrificed at 6 and 12 weeks after transplantation. Repaired tissues were evaluated via gross examination, histologic examination, and immunohistochemistry. RESULTS: In vitro, this aptamer-functionalized scaffold could recruit bone marrow-derived MSCs and support cell adhesion. In vivo, the aptamer-functionalized scaffold enhanced cell homing in comparison with the aptamer-free scaffold. The aptamer-functionalized scaffold group also exhibited superior cartilage restoration when compared with the scaffold-only group and the control group. CONCLUSION: The Apt19s-functionalized scaffold exhibited the ability to recruit MSCs both in vitro and in vivo and achieved a better outcome of cartilage repair than the scaffold only or control in an osteochondral defect model. CLINICAL RELEVANCE: The findings demonstrate a promising strategy of using aptamer-functionalized bioscaffolds for restoration of chondral/osteochondral defects via aptamer-introduced homing of MSCs.
BACKGROUND: Recruitment of endogenous stem cells has been considered an alternative to cell injection/implantation in articular cartilage repair. PURPOSE: (1) To develop a cartilage tissue-engineering scaffold with clinically available biomaterials and functionalize the scaffold with an aptamer (Apt19s) that specifically recognizes pluripotent stem cells. (2) To determine whether this scaffold could recruit joint-resident mesenchymal stem cells (MSCs) when implanted into an osteochondral defect in a rabbit model and to examine the effects of cartilage regeneration. STUDY DESIGN: Controlled laboratory study. METHODS: The reinforced scaffold was fabricated by embedding a silk fibroin sponge into silk fibroin/hyaluronic acid-tyramine hydrogel and characterized in vitro. A cylindrical osteochondral defect (3.2 mm wide × 4 mm deep) was created in the trochlear grooves of rabbit knees. The rabbits were randomly assigned into 3 groups: Apt19s-functionalized scaffold group, scaffold-only group, and control group. Animals were sacrificed at 6 and 12 weeks after transplantation. Repaired tissues were evaluated via gross examination, histologic examination, and immunohistochemistry. RESULTS: In vitro, this aptamer-functionalized scaffold could recruit bone marrow-derived MSCs and support cell adhesion. In vivo, the aptamer-functionalized scaffold enhanced cell homing in comparison with the aptamer-free scaffold. The aptamer-functionalized scaffold group also exhibited superior cartilage restoration when compared with the scaffold-only group and the control group. CONCLUSION: The Apt19s-functionalized scaffold exhibited the ability to recruit MSCs both in vitro and in vivo and achieved a better outcome of cartilage repair than the scaffold only or control in an osteochondral defect model. CLINICAL RELEVANCE: The findings demonstrate a promising strategy of using aptamer-functionalized bioscaffolds for restoration of chondral/osteochondral defects via aptamer-introduced homing of MSCs.
Authors: Yangyi Yu; Francisco Rodriguez-Fontan; Kevin Eckstein; Archish Muralidharan; Asais Camila Uzcategui; Joseph R Fuchs; Shane Weatherford; Christopher B Erickson; Stephanie J Bryant; Virginia L Ferguson; Nancy Hadley Miller; Guangheng Li; Karin A Payne Journal: Tissue Eng Part C Methods Date: 2019-10-31 Impact factor: 3.056