Porous scaffolds of a polymer-bioceramics composite repair bonds via in vivo tissue engineering

Poly(lactic-co-glycolic acid) (PLGA) is excellent as a scaffolding matrix due to feasibility of processing and tunable biodegradability, yet the virgin scaffolds lack osteoconduction and osteoinduction. In this study, nano-hydroxyapatite (nHA) was coated on the interior surfaces of PLGA scaffolds in order to facilitate in vivo bone defect restoration using biomimetic ceramics while keeping the polyester skeleton of the scaffolds.

SEM images on interior surfaces of PLGA porous scaffolds coated with nHA

The constructs of scaffolds and autogenous bone marrow stromal cells were implanted into the segmental bone defect in the rabbit model, and a successful bone regeneration was achieved. This work was made in cooperation with a surgeon group led by Professor Guoxian PEI. The article with Mr. Yao HE, a Ph. D student from Ding Group as a co-first author was published in Int. J. Nanomed.

Histological images and histomorphometric analysis of bone formation.

Merged histological micrographs of sections upon van Gieson staining. The tissue stained in red is the newly formed bone with visible cell nuclei. The tissue stained in yellow/black indicates the fibrous tissue and undegraded material. After 4 weeks, callus were eugenic in Groups A and B. After 8 weeks, a callus mass was absorbed in Group A, while significant callus still remained in Group B. After 12 weeks, nHA coated PLGA scaffolds showed a better result. As depicted in the images, whole bone cortex was regenerated in Group A at the 12th week, and the medullary cavity was reformed.

l  Enhancing the bioactivity of Poly(lactic-co-glycolic acid) scaffold with a nano-hydroxyapatite coating for the treatment of segmental bone defect in a rabbit model

De-Xin Wang, Yao He (co-first author), Long Bi (co-first author), Ze-Hua Qu, Ji-Wei Zou, Zhen Pan, Jun-Jun Fan, Liang Chen, Xin Dong, Xiang-Nan Liu, Guo-Xian Pei*, and Jiandong Ding*, Int. J. Nanomed., 8: 1855–1865 (2013)