Haifeng Wang Chenhui Zhou Yi Huang Fanyong Gong Jianyong Wang Xiang Gao ^*

• Department of Neurosurgery, The First Affiliated Hospital of Ningbo University, Ningbo, China

Background: The utilization of vascular endothelial growth factor (VEGF) in its early stages to facilitate prompt endothelialization is a significant approach in the prevention of thrombosis in small-diameter vascular grafts (SDVGs). QKCMP, a chemically modified form of VEGF that exhibits strong affinity for collagen, is highly suitable for engineering purposes. This investigation focuses on the design of a prototype for a rapid endothelialization SDVG utilizing QKCMP, and aims to elucidate the mechanisms responsible for its facilitation of rapid endothelialization. Methods: SDVG prototypes were manufactured for the purpose of evaluating the utilization of QKCMP on the stent. The release properties of platelet-derived growth factor (PDGF) from the SDVG prototype, the durability of collagen-gelatin (Col-Gel) films, and the stability of VEGF/QKCMP were subjected to testing. A Transwell co-culture system was established, and the early promoting effect of QKCMP was verified in vitro through the employment of the CCK-8 assay. Cell growth curves, apoptosis, and cell cycle were assessed using phase-contrast microscopy and flow cytometry. The genetic mechanisms and signaling pathways involved in the facilitation of in vitro rapid endothelialization by QKCMP were investigated using RNA sequencing (RNA-seq) analysis. Results: The experimental results show that the physical and biological properties of SDVG with QKCMP, such as tensile properties, packaging efficiency, stability and release behavior, meet the requirements. The performance of the SDVG prototype incorporating QKCMP is better than that of ordinary SDVG prototype. In transwell co-culture systems, HUVECs’ fast growth in early stage in BQ and PQ, lowest rate of cell apoptosis rate in PQ, and more G2 and S phases in PQ and BQ were observed. RNA-seq analysis showed that the VEGFA-VEGFR2 signaling pathway and Hippo signaling pathway were associated with rapid endothelialization of QKCMP in vitro. And two key genes were identified. Conclusion: It was effective and adequate of QKCMP applying in SDVG prototype for rapid endothelial purpose. RNA-seq investigation deeply revealed the genetic mechanism and signal pathways of HUVECs’ rapid proliferation promoted by QKCMP. Next stage, it was necessary to make a fundamental improvement of SDVG and assess rapid endothelialization by QKCMP in vivo.