TCP/PLGA composite scaffold loaded rapamycin in situ enhances lumbar fusion by regulating osteoblast and osteoclast activity

Abstract

The purpose of this study was to develop a novel β-tricalcium phosphate (TCP)/poly (D,L-lactic-co-glycolic acid) (PLGA) composite scaffold loaded with rapamycin that can regulate the activity of osteoblasts and osteoclasts for lumbar fusion. The TCP/ PLGA composite scaffold was fabricated by cryogenic three-dimensional printing techniques and then loaded with rapamycin in situ. The structural surface morphology of the composite scaffold was tested with scanning electron microscope. To evaluate the biocompatibility of the composite scaffold in vitro, bone marrow mesenchymal stem cells (BMSCs) were cultured on the TCP/PLGA composite scaffold slide and tested with Live/Dead Viability Kit. The effect of rapamycin on osteoclast and osteoblast was studied with staining and Western blotting. The in vitro results showed that the rapamycin-loaded TCP/PLGA composite scaffold showed good biocompatibility with BMSC and released rapamycin obviously promoted the osteoblast differentiation and mineralization. In vivo study, the TCP/ PLGA composite scaffold loaded with rapamycin were implanted in lumbar fusion model and study with micro-computed tomography scanning, hematoxylin-eosin, Masson, and immune-histological staining, to evaluate the effect of rapamycin on bone fusion. The in vivo results demonstrated that rapamycin-loaded TCP/PLGA composite scaffold could enhance bone formation by regulating osteoblast and osteoclast activity, respectively. In this study, the TCP/PLGA composite scaffold loaded with rapamycin was confirmed to provide great compatibility and improved performance in lumbar fusion by regulating osteoblastic and osteoclastic activity and would be a promising composite biomaterial for bone tissue engineering.

Enhancing autophagy and energy metabolism in the meniscus can delay the occurrence of PTOA in ACLT rat

“…HE staining and toluidine blue staining were carried out concerning previous literature reports (Liu et al, 2021;Yan et al, 2021). In short, for HE staining, select paraffin sections with clear joint structure, then place them in a 65 °C oven for 1 h and then perform a series of dewaxing and hydration steps.…”

“…Immunohistochemical staining and immunofluorescence staining were carried out regarding previous literature reports (Liu et al, 2021;Suo et al, 2022). The steps of section selection, baking, dewaxing and hydration are the same as those of HE staining.…”

Vancomycin Containing PDLLA and PLGA/β-TCP Inhibit Biofilm Formation but Do Not Stimulate Osteogenic Transformation of Human Mesenchymal Stem Cells

“…PLGA was also assessed for its osteogenic potential in a study by Yoon et al (18). β-TCP was studied as a drug carrier (19), and a study (20) focused on the osteogenic potential of the material previously. We hypothesized that vancomycin containing PDLLA/β-TCP and PLGA/β-TCP composites will stimulate osteogenesis due to its high β-TCP content.…”