Decellularized extracellular matrix Polycaprolactone/Chitosan composite nanofibrous scaffolds for periodontal tissue engineering

Periodontitis is an inflammatory infection caused by bacterial plaque accumulation that affects the periodontal tissues supporting the teeth. Current treatments lack bioactive signals to induce tissue repair and coordinated regeneration of the periodontal tissues, thus alternative strategies are needed to improve clinical outcomes. Cell-derived extracellular matrix (ECM) has been used in combination with biomaterials to enhance their biofunctionality for various tissue engineering (TE) applications. In this work, bioactive cell-derived ECM loaded electrospun polycaprolactone/chitosan (PCL-CTS) nanofibrous scaffolds were developed using lyophilized decellularized ECM (dECM) derived from human Periodontal Ligament Stem Cells (hPDLSCs). This work's aims were to fabricate and characterize cell-derived ECM electrospun PCL-CTS scaffolds and assess their ability to enhance the osteogenic differentiation of hPDLSCs, envisaging periodontal TE applications. hPDLSCs were cultured and used for dECM production, aiming to recreate the periodontal niche. The physicochemical properties of electrospun scaffolds were assessed (structure, elemental composition, hydrophilicity, thermal and mechanical properties) and the effects of CTS and dECM presence on the scaffolds' properties were determined. PCL-CTS and PCL-CTS-ECM scaffolds were composed of homogeneous beadless nanofibers. Osteogenic differentiation of hPDLSCs was performed on PCL, PCL-CTS and PCL-CTS-ECM electrospun scaffolds for 21 days. The obtained results demonstrate that PCL-CTS-ECM scaffolds significantly enhanced cell proliferation compared to PCL and PCL-CTS scaffolds, while maintaining similar physical and mechanical properties of PCL-CTS scaffolds. PCL-CTS scaffolds showed higher levels of calcium deposition and cell mineralization than PCL scaffolds. PCL-CTS-ECM scaffolds enhanced the osteogenic differentiation of hPDLSCs as confirmed by increased alkaline phosphatase (ALP) activity, calcium deposition and upregulation of osteogenic marker-genes. Overall, our results show that ECM loaded electrospun nanofibrous scaffolds enhanced the proliferation and osteogenic differentiation of hPDLSCs. Notably, this work describes the first use of lyophilized cell-derived ECM loaded electrospun scaffolds for periodontal TE applications and highlights its potential as a promising therapeutic strategy for periodontitis.