Rapid fabrication of biomimetic PLGA microsphere incorporated with natural porcine dermal aECM for bone regeneration.

Abstract

Bioactive microspheres coated with acellular extracellular matrix (aECM) have received extensive attention in bone tissue engineering. In this work, biomimetic microspheres with different aECM ratios, uniform size and controllable size were prepared easily by blending natural porcine dermal aECM and poly (lactic-co-glycolic acid) (PLGA) using electrohydrodynamic spraying and solidification actuated by solvent extraction method. In this work, the appropriate polymer concentration and preparation voltage were investigated, and the surface morphology of the microspheres was observed by scanning electron microscope. Sirius red was used to visualize aECM exposure on the surface of the microspheres. The in vitro and in vivo experiments were carried out to evaluate the bioactivity and osteogenic properties of the microspheres. The results showed that the morphology and size of PLGA microspheres had little influence on the aECM blending. In vitro experiments showed that the higher the content of aECM, the better the cell adhesion performance. In vivo, rat calvarial defect models were observed and characterized at 4 and 8 weeks postoperatively, and the values of BV/TV of 50aECM/PLGA were 47.57 ± 1.14% and 72.92 ± 2.19%, respectively. The results showed that the skull healing effect was better in aECM-containing microspheres. In conclusion, aECM/PLGA composite microspheres can increase cell adhesion performance through the addition of aECM. Moreover, in vivo experiments have proved that aECM/PLGA microspheres are beneficial to bone repair, which means the aECM/PLGA microspheres are a promising bone tissue engineering material.