Injectable adipose-derived stem cells-embedded alginate-gelatin microspheres prepared by electrospray for cartilage tissue regeneration

Sida Liao; Haoye Meng; Jun Zhao; Wancheng Lin; Xiuzhi Liu; Zhuang Tian; Lan Lan; Hanyu Yang; Yulan Zou; Yichi Xu; Xiao Gao; Shibi Lu; Jiang Peng

doi:10.1016/j.jot.2022.03.007

Injectable adipose-derived stem cells-embedded alginate-gelatin microspheres prepared by electrospray for cartilage tissue regeneration

J Orthop Translat. 2022 Apr 11:33:174-185. doi: 10.1016/j.jot.2022.03.007. eCollection 2022 Mar.

Authors

Sida Liao^{1

2}, Haoye Meng¹, Jun Zhao¹, Wancheng Lin¹, Xiuzhi Liu¹, Zhuang Tian¹, Lan Lan², Hanyu Yang², Yulan Zou³, Yichi Xu¹, Xiao Gao¹, Shibi Lu¹, Jiang Peng¹

Affiliations

¹ Institute of Orthopedics/ Beijing Key Laboratory of Regenerative Medicine in Orthopedics/ Key Laboratory of Musculoskeletal Trauma & War Injuries PLA, Chinese PLA General Hospital, Beijing, 100853, China.
² Department of Anesthesiology, The First Affiliated Hospital of Guangzhou Medical University, China (mainland), Guangzhou, 510120, China.
³ Department of Anesthesiology, Guangzhou Red Cross Hospital, China (mainland), Guangzhou, 510240, China.

Abstract

Objective: To prepare adipose-derived stem cells (ADSCs)-embedded alginate-gelatinemicrospheres (Alg-Gel-ADSCs MSs) by electrospray and evaluate their feasibility for cartilage tissue engineering. To observe the efficacy of Alg-Gel-ADSCs MSs in repairing articular cartilage defects in SD rats.

Methods: ADSCs were isolated and characterized by performing induced differentiation and flow cytometry assays. Alginate-gelatine microspheres with different gelatine concentrations were manufactured by electrospraying, and the appropriate alginate-gelatine concentration and ratio were determined by evaluating microsphere formation. Alg-Gel-ADSCs MSs were compared with Alg-ADSCs MSs through the induction of chondrogenic differentiation and culture. Their feasibility for cartilage tissue engineering was analysed by performing Live/Dead staining, cell proliferation analysis, toluidine blue staining and a glycosaminoglycan (GAG) content analysis. Alg-Gel-ADSCs MSs were implanted in the cartilage defects of SD rats, and the cartilage repair effect was evaluated at different time points. The evaluation included gross observations and histological evaluations, fluorescence imaging tracking, immunohistochemical staining, microcomputed tomography (micro-CT) and a CatWalk evaluation.

Results: The isolated ADSCs showed multidirectional differentiation and were used for cartilage tissue engineering. Using 1.5 w:v% alginate and 0.5 w:v% gelatine (Type B), we successfully prepared nearly spherical microspheres. Compared with alginate microspheres, alginate gel increased the viability of ADSCs and promoted the proliferation and chondrogenesis of ADSCs. In our experiments on knee cartilage defects in SD rats in vivo, the Alg-Gel-ADSCs MSs showed superior cartilage repair in cell resides, histology evaluation, micro-CT imaging and gait analysis.

Conclusions: Microspheres composed of 1.5 w:v% alginate-0.5 w:v% gelatine increase the viability of ADSCs and supported their proliferation and deposition of cartilage matrix components. ADSCs embedded in 1.5 w:v% alginate-0.5 w:v% gelatine microspheres show superior repair efficacy and prospective applications in cartilage tissue repair.

The translational potential of this article: In this study, injectable adipose-derived stem cells-embedded alginate-gelatin microspheres (Alg-Gel-ADSCs MSs) were prepared by the electrospray . Compared with the traditional alginate microspheres, its support ability for ADSCs is better and shows a better repair effect. This study provides a promising strategy for cartilage tissue regeneration.

Keywords: Alginate-gelatine; Biofabrication; Cartilage regeneration; Electrospray.