关键词: 静电纺丝, 纳米纤维支架, 免疫调节, 巨噬细胞, 牙周炎

Abstract:

Objective To synthesize mesoporous bioactive glass nanoparticles(MBGN)-enhanced poly-caprolactone(PCL)electrospun nanofiber 3D bone tissue engineering(BTE) scaffolds and to investigate the in vitro anti-inflammatory function of this scaffold. Methods PCL membranes were obtained by electrospinning; MBGN was synthesized by sol-gel method, and the MBGN-enhanced PCL electrospun nanofiber 3D bone tissue engineering scaffold PCL@MBGN was synthesized by dispersion, homogenization, filtering, freeze-drying, thermal self-assembly of gelatin, and surface modification with carboxymethyl chitosan, etc. The scaffolds were characterized by scanning electron microscopy and energy dispersive spectrometer. CCK-8 assay and live/dead staining assay were used to detect the biocompatibility of the scaffolds. Lipopolysaccharide(LPS) was used to stimulate RAW264.7 cells for 12 h to induce polarization toward M1 type, and then PCL@MBGN extracts with different MBGN additions were used to stimulate cells for 48 h. The expression level characteristic surface markers of M1 and M2 macrophages, CD86 and CD206, were detected by flow cytometry. qRT-PCR was used to detect the transcriptional levels of inflammation-related cytokines such as tumor necrosis factor alpha(TNF-α), interleukin-1 beta(IL-1β), interleukin-4(IL-4), inducible nitric oxide synthase(iNOS), and other cytokines. Results With the increase of MBGN addition, the spherical particles on the fiber surface increased under SEM, but did not significantly affect the macroscopic morphology of the scaffolds. PCL@MBGN not only possessed good in vitro biocompatibility, but also inhibited LPS-induced polarization of pro-inflammatory M1 macrophages (P<0.01). To some extent, the scaffolds promoted the polarization of anti-inflammatory M2 macrophages (P<0.01), inhibited the transcription of pro-inflammatory cytokines, including IL-1β, TNF-α and iNOs (P<0.05), and promoted the transcription of anti-inflammatory cytokine IL-4 (P<0.05), exerting an in vitro anti-inflammatory effect. Conclusion In this study, a nanofibrous scaffold PCL@MBGN with 3D structure was successfully prepared. The addition of MBGN did not significantly affect the morphology of the scaffold. The scaffolds were non-cytotoxic, had anti-inflammatory effects. The results suggest that PCL@MBGN has great potential for application in bone defect repair in inflammatory environments.

Key words: electrospinning, nanofiberous scaffold, immunomodulation, macrophages, periodontitis