Three dimensional nanofibrous and compressible poly(L-lactic acid) bone grafts loaded with platelet-rich plasma

Biomed Mater. 2021 Apr 9;16(4). doi: 10.1088/1748-605X/abef5a.

Abstract

In this study, nanofibrous matrices of poly(L-lactic acid)-hydroxyapatite (PLLA-HAp) were successfully fabricated by three-dimensional (3D) electrospinning for use in the treatment of irregular bone damages. Compressibility analysis showed that 3D nanofibrous grafts occupied at least 2-fold more volume than their 2D form and they can easily take shape of the defect zone with irregular geometry. Moreover, the compression moduli of the PLLA and PLLA-HAp grafts were calculated as 8.0 ± 3.0 kPa and 11.8 ± 3.9 kPa, respectively, while the strain values of the same samples at the maximum load of 600 kPa were 164 ± 28% and 130 ± 20%, respectively. Treatment of the grafts with aqueous sodium hydroxide solution increased the surface roughness and thus the alloplastic graft materials (PLLA-HAp/M) protecting the fiber morphology were produced successfully. Then, platelet-rich plasma (PRP) was loaded into the surface modified grafts and activated with 10% calcium chloride. The efficiency of the activation was evaluated with flow cytometry and it was found that after activation the percentages of CD62 (P-selectin) and CD41/61 (glycoprotein IIb/IIIa) proteins increased approximately 4-fold. Surface hydrophilicity and biological activity of the PLLA-HAp grafts were enhanced by fibrin coating after PRP activation. Thein vitrocell culture studies which were carried out by using mouse pre-osteoblasts (MC3T3-E1) showed that graft materials supported by PRP increased cellular proliferation and osteogenic differentiation significantly. Thein vivoresults demonstrated that compared with bare PLLA-HAp/M grafts, the PRP loaded grafts (PRP-PLLA-HAp/M) induced significantly greater bone formation based on computed tomography, histological and immunohistochemical analyses. Our findings suggest that 3D PLLA nanofibrous matrices can be used as a graft material for irregular bone defects especially when combined with PRP as an osteogenic induction agent.

Keywords: bone tissue engineering; hydroxyapatite; platelet-rich plasma; poly(L-lactic acid); three-dimensional electrospinning.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Animals
  • Bone Substitutes* / chemistry
  • Bone Substitutes* / pharmacology
  • Bone and Bones / cytology
  • Bone and Bones / metabolism
  • Cell Line
  • Durapatite
  • Electrochemical Techniques
  • Humans
  • Male
  • Mice
  • Nanofibers / chemistry*
  • Osteoblasts / cytology
  • Osteogenesis / drug effects*
  • Platelet-Rich Plasma / chemistry*
  • Polyesters* / chemistry
  • Polyesters* / pharmacology
  • Tissue Engineering

Substances

  • Bone Substitutes
  • Polyesters
  • poly(lactide)
  • Durapatite